International Journal of Molecular Sciences

2024

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21 pages, 9562 KiB

Open AccessArticle

Multifunctional Sr,Mg-Doped Mesoporous Bioactive Glass Nanoparticles for Simultaneous Bone Regeneration and Drug Delivery

by Tamara Matic, Farah Daou, Andrea Cochis, Nemanja Barac, Vukasin Ugrinovic, Lia Rimondini and Djordje Veljovic

Int. J. Mol. Sci. 2024, 25(15), 8066; https://doi.org/10.3390/ijms25158066 - 24 Jul 2024

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Abstract

Mesoporous bioactive glass nanoparticles (MBGNs) doped with therapeutical ions present multifunctional systems that enable a synergistic outcome through the dual delivery of drugs and ions. The aim of this study was to evaluate influence of co-doping with strontium and magnesium ions (SrMg-MBGNs) on [...] Read more.

Mesoporous bioactive glass nanoparticles (MBGNs) doped with therapeutical ions present multifunctional systems that enable a synergistic outcome through the dual delivery of drugs and ions. The aim of this study was to evaluate influence of co-doping with strontium and magnesium ions (SrMg-MBGNs) on the properties of MBGNs. A modified microemulsion-assisted sol–gel synthesis was used to obtain particles, and their physicochemical properties, bioactivity, and drug-loading/release ability were evaluated. Indirect biological assays using 2D and 3D cell culture models on human bone marrow-derived mesenchymal stem cells (hBM-MSCs) and endothelial EA.hy926 cells, respectively, were used to determine biocompatibility of MBGNs, their influence on alkaline phosphatase (ALP) production, calcium deposition, and cytoskeletal organization. Results showed that Sr,Mg-doping increased pore volume and solubility, and changed the mesoporous structure from worm-like to radial–dendritic, which led to a slightly accelerated drug release compared to pristine MBGNs. Biological assays confirmed that particles are biocompatible, and have ability to slightly induce ALP production and calcium deposition of hBM-MSCs, as well as to significantly improve the proliferation of EA.hy926 compared to biochemical stimulation via vascular endothelial growth factor (VEGF) administration or regular media. Fluorescence staining revealed that SrMg-MBGNs had a similar effect on EA.hy926 cytoskeletal organization to the VEGF group. In conclusion, Sr,Mg-MBGNs might be considered promising biomaterial for biomedical applications. Full article

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16 pages, 6505 KiB

Open AccessArticle

Effect of Solvent Properties on the Critical Solution Temperature of Thermoresponsive Polymers

by Konstantin Nikolaus Beitl and Erik Reimhult

Int. J. Mol. Sci. 2024, 25(14), 7734; https://doi.org/10.3390/ijms25147734 - 15 Jul 2024

Cited by 1 | Viewed by 876

Abstract

The ability of thermoresponsive polymers to respond to temperature with a reversible conformational change makes them promising ‘smart’ materials for solutions in medical and biotechnological applications. In this work, two such polymers and structural isomers were studied: poly(N-isopropyl acrylamide) (PNiPAm) and [...] Read more.

The ability of thermoresponsive polymers to respond to temperature with a reversible conformational change makes them promising ‘smart’ materials for solutions in medical and biotechnological applications. In this work, two such polymers and structural isomers were studied: poly(N-isopropyl acrylamide) (PNiPAm) and poly(2-isopropyl-2-oxazoline) (PiPOx). We compare the critical solution temperatures (CST) of these polymers in D₂O and H₂O in the presence of Hofmeister series salts, as results obtained under these different solvent conditions are often compared. D₂O has a higher dipole moment and electronegativity than H₂O, which could significantly alter the CST transition. We used two complementary methods to measure the CST, dynamic light scattering (DLS) and differential scanning calorimetry (DSC) and found that the CST decreased significantly in D₂O compared to H₂O. In the presence of highly concentrated kosmotropes, the CST of both polymers decreased in both solvents. The influence of the kosmotropic anions was smaller than the water isotope effect at low ionic strengths but considerably higher at physiological ionic strengths. However, the Hofmeister anion effect was quantitatively different in H₂O than in D₂O, with the largest relative differences observed for Cl⁻, where the CSTs in D₂O decreased more than in H₂O measured by DLS but less by DSC. PiPOx was more sensitive than PNiPAm to the presence of chaotropes. It exhibited much higher transition enthalpies and multistep transitions, especially in aqueous solutions. Our results highlight that measurements of thermoresponsive polymer properties in D₂O cannot be compared directly or quantitatively to application conditions or even measurements performed in H₂O. Full article

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17 pages, 2996 KiB

Open AccessArticle

Influence of the Surface Topography of Titanium Dental Implants on the Behavior of Human Amniotic Stem Cells

by Rodrigo Riedel, Soledad Pérez-Amodio, Laura Cabo-Zabala, Eugenio Velasco-Ortega, Julieta Maymó, Javier Gil, Loreto Monsalve-Guil, Iván Ortiz-Garcia, Antonio Pérez-Pérez, Victor Sánchez-Margalet and Alvaro Jiménez-Guerra

Int. J. Mol. Sci. 2024, 25(13), 7416; https://doi.org/10.3390/ijms25137416 - 6 Jul 2024

Viewed by 947

Abstract

The dental implant surface plays a crucial role in osseointegration. The topography and physicochemical properties will affect the cellular functions. In this research, four distinct titanium surfaces have been studied: machined acting (MACH), acid etched (AE), grit blasting (GBLAST), and a combination of [...] Read more.

The dental implant surface plays a crucial role in osseointegration. The topography and physicochemical properties will affect the cellular functions. In this research, four distinct titanium surfaces have been studied: machined acting (MACH), acid etched (AE), grit blasting (GBLAST), and a combination of grit blasting and subsequent acid etching (GBLAST + AE). Human amniotic mesenchymal (hAMSCs) and epithelial stem cells (hAECs) isolated from the amniotic membrane have attractive stem-cell properties. They were cultured on titanium surfaces to analyze their impact on biological behavior. The surface roughness, microhardness, wettability, and surface energy were analyzed using interferometric microscopy, Vickers indentation, and drop-sessile techniques. The GBLAST and GBLAST + AE surfaces showed higher roughness, reduced hydrophilicity, and lower surface energy with significant differences. Increased microhardness values for GBLAST and GBLAST + AE implants were attributed to surface compression. Cell viability was higher for hAMSCs, particularly on GBLAST and GBLAST + AE surfaces. Alkaline phosphatase activity enhanced in hAMSCs cultured on GBLAST and GBLAST + AE surfaces, while hAECs showed no mineralization signals. Osteogenic gene expression was upregulated in hAMSCs on GBLAST surfaces. Moreover, α2 and β1 integrin expression enhanced in hAMSCs, suggesting a surface−integrin interaction. Consequently, hAMSCs would tend toward osteoblastic differentiation on grit-blasted surfaces conducive to osseointegration, a phenomenon not observed in hAECs. Full article

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11 pages, 3046 KiB

Open AccessArticle

Degradation of Toxins Derived from Foodborne Pathogens by Atmospheric-Pressure Dielectric-Barrier Discharge

by Akikazu Sakudo and Yoshihito Yagyu

Int. J. Mol. Sci. 2024, 25(11), 5986; https://doi.org/10.3390/ijms25115986 - 30 May 2024

Viewed by 814

Abstract

Foodborne diseases can be attributed not only to contamination with bacterial or fungal pathogens but also their associated toxins. Thus, to maintain food safety, innovative decontamination techniques for toxins are required. We previously demonstrated that an atmospheric-pressure dielectric-barrier discharge (APDBD) plasma generated by [...] Read more.

Foodborne diseases can be attributed not only to contamination with bacterial or fungal pathogens but also their associated toxins. Thus, to maintain food safety, innovative decontamination techniques for toxins are required. We previously demonstrated that an atmospheric-pressure dielectric-barrier discharge (APDBD) plasma generated by a roller conveyer plasma device is effective at inactivating bacteria and fungi in foods. Here, we have further examined whether the roller conveyer plasma device can be used to degrade toxins produced by foodborne bacterial pathogens, including aflatoxin, Shiga toxins (Stx1 and Stx2), enterotoxin B and cereulide. Each toxin was spotted onto an aluminum plate, allowed to dry, and then treated with APDBD plasma applied by the roller conveyer plasma device for different time periods. Assessments were conducted using a competitive enzyme-linked immunosorbent assay (ELISA) and liquid chromatography–tandem mass spectrometry (LC-MS/MS). The results demonstrate a significant time-dependent decrease in the levels of these toxins. ELISA showed that aflatoxin B₁ concentrations were reduced from 308.6 µg/mL to 74.4 µg/mL within 1 min. For Shiga toxins, Stx1 decreased from 913.8 µg/mL to 65.1 µg/mL, and Stx2 from 2309.0 µg/mL to 187.6 µg/mL within the same time frame (1 min). Enterotoxin B levels dropped from 62.67 µg/mL to 1.74 µg/mL at 15 min, and 1.43 µg/mL at 30 min, but did not display a significant decrease within 5 min. LC-MS/MS analysis verified that cereulide was reduced to below the detection limit following 30 min of APDBD plasma treatment. Taken together, these findings highlight that a range of foodborne toxins can be degraded by a relatively short exposure to plasma generated by an APDBD using a roller conveyer device. This technology offers promising advancements in food safety, providing a novel method to alleviate toxin contamination in the food processing industry. Full article

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23 pages, 2316 KiB

Open AccessReview

Dentin Mechanobiology: Bridging the Gap between Architecture and Function

by Xiangting Fu and Hye Sung Kim

Int. J. Mol. Sci. 2024, 25(11), 5642; https://doi.org/10.3390/ijms25115642 - 22 May 2024

Viewed by 1249

Abstract

It is remarkable how teeth maintain their healthy condition under exceptionally high levels of mechanical loading. This suggests the presence of inherent mechanical adaptation mechanisms within their structure to counter constant stress. Dentin, situated between enamel and pulp, plays a crucial role in [...] Read more.

It is remarkable how teeth maintain their healthy condition under exceptionally high levels of mechanical loading. This suggests the presence of inherent mechanical adaptation mechanisms within their structure to counter constant stress. Dentin, situated between enamel and pulp, plays a crucial role in mechanically supporting tooth function. Its intermediate stiffness and viscoelastic properties, attributed to its mineralized, nanofibrous extracellular matrix, provide flexibility, strength, and rigidity, enabling it to withstand mechanical loading without fracturing. Moreover, dentin’s unique architectural features, such as odontoblast processes within dentinal tubules and spatial compartmentalization between odontoblasts in dentin and sensory neurons in pulp, contribute to a distinctive sensory perception of external stimuli while acting as a defensive barrier for the dentin-pulp complex. Since dentin’s architecture governs its functions in nociception and repair in response to mechanical stimuli, understanding dentin mechanobiology is crucial for developing treatments for pain management in dentin-associated diseases and dentin-pulp regeneration. This review discusses how dentin’s physical features regulate mechano-sensing, focusing on mechano-sensitive ion channels. Additionally, we explore advanced in vitro platforms that mimic dentin’s physical features, providing deeper insights into fundamental mechanobiological phenomena and laying the groundwork for effective mechano-therapeutic strategies for dentinal diseases. Full article

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23 pages, 1765 KiB

Open AccessPerspective

Graphene and Natural Products: A Review of Antioxidant Properties in Graphene Oxide Reduction

by Filipe Kayodè Felisberto dos Santos, Antônio Augusto Martins Pereira Júnior, Arquimedes Lopes Nunes Filho, Clícia Joanna Neves Fonseca, Daysianne Kessy Mendes Isidorio, Filipe de Almeida Araújo, Pablo Henrique Ataide Oliveira and Valdir Florêncio da Veiga Júnior

Int. J. Mol. Sci. 2024, 25(10), 5182; https://doi.org/10.3390/ijms25105182 - 9 May 2024

Cited by 5 | Viewed by 1933

Abstract

This review article addresses the antioxidant properties of different natural products, including ascorbic acid, gallic acid, oxalic acid, L-glutathione (GSH), bacteriorhodopsin, green tea polyphenols, glucose, hydroxycinnamic acid, ethanoic acid, betanin, and L-glutathione, in the reduction of graphene oxide (rGO). rGO can cause damage [...] Read more.

This review article addresses the antioxidant properties of different natural products, including ascorbic acid, gallic acid, oxalic acid, L-glutathione (GSH), bacteriorhodopsin, green tea polyphenols, glucose, hydroxycinnamic acid, ethanoic acid, betanin, and L-glutathione, in the reduction of graphene oxide (rGO). rGO can cause damage to cells, including oxidative stress and inflammation, limiting its application in different sectors that use graphene, such as technologies used in medicine and dentistry. The natural substances reviewed have properties that help reduce this damage, neutralizing free radicals and maintaining cellular integrity. This survey demonstrates that the combination of these antioxidant compounds can be an effective strategy to minimize the harmful effects of rGO and promote cellular health. Full article

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22 pages, 13529 KiB

Open AccessArticle

Exploring the Effect of V₂O₅ and Nb₂O₅ Content on the Structural, Thermal, and Electrical Characteristics of Sodium Phosphate Glasses and Glass–Ceramics

by Sara Marijan, Teodoro Klaser, Marija Mirosavljević, Petr Mošner, Ladislav Koudelka, Željko Skoko, Jana Pisk and Luka Pavić

Int. J. Mol. Sci. 2024, 25(5), 3005; https://doi.org/10.3390/ijms25053005 - 5 Mar 2024

Cited by 1 | Viewed by 1603

Abstract

Na-V-P-Nb-based materials have gained substantial recognition as cathode materials in high-rate sodium-ion batteries due to their unique properties and compositions, comprising both alkali and transition metal ions, which allow them to exhibit a mixed ionic–polaronic conduction mechanism. In this study, the impact of [...] Read more.

Na-V-P-Nb-based materials have gained substantial recognition as cathode materials in high-rate sodium-ion batteries due to their unique properties and compositions, comprising both alkali and transition metal ions, which allow them to exhibit a mixed ionic–polaronic conduction mechanism. In this study, the impact of introducing two transition metal oxides, V₂O₅ and Nb₂O₅, on the thermal, (micro)structural, and electrical properties of the 35Na₂O-25V₂O₅-(40 − x)P₂O₅ − xNb₂O₅ system is examined. The starting glass shows the highest values of DC conductivity, σ_DC, reaching 1.45 × 10⁻⁸ Ω⁻¹ cm⁻¹ at 303 K, along with a glass transition temperature, T_g, of 371 °C. The incorporation of Nb₂O₅ influences both σ_DC and T_g, resulting in non-linear trends, with the lowest values observed for the glass with x = 20 mol%. Electron paramagnetic resonance measurements and vibrational spectroscopy results suggest that the observed non-monotonic trend in σ_DC arises from a diminishing contribution of polaronic conductivity due to the decrease in the relative number of V⁴⁺ ions and the introduction of Nb₂O₅, which disrupts the predominantly mixed vanadate–phosphate network within the starting glasses, consequently impeding polaronic transport. The mechanism of electrical transport is investigated using the model-free Summerfield scaling procedure, revealing the presence of mixed ionic–polaronic conductivity in glasses where x < 10 mol%, whereas for x ≥ 10 mol%, the ionic conductivity mechanism becomes prominent. To assess the impact of the V₂O₅ content on the electrical transport mechanism, a comparative analysis of two analogue series with varying V₂O₅ content (10 and 25 mol%) is conducted to evaluate the extent of its polaronic contribution. Full article

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23 pages, 3854 KiB

Open AccessArticle

Integrated Experimental and Mathematical Exploration of Modular Tissue Cultures for Developmental Engineering

by Tao Sun, Yu Xiang, Freya Turner and Xujin Bao

Int. J. Mol. Sci. 2024, 25(5), 2987; https://doi.org/10.3390/ijms25052987 - 4 Mar 2024

Viewed by 979

Abstract

Developmental engineering (DE) involves culturing various cells on modular scaffolds (MSs), yielding modular tissues (MTs) assembled into three-dimensional (3D) tissues, mimicking developmental biology. This study employs an integrated approach, merging experimental and mathematical methods to investigate the biological processes in MT cultivation and [...] Read more.

Developmental engineering (DE) involves culturing various cells on modular scaffolds (MSs), yielding modular tissues (MTs) assembled into three-dimensional (3D) tissues, mimicking developmental biology. This study employs an integrated approach, merging experimental and mathematical methods to investigate the biological processes in MT cultivation and assembly. Human dermal fibroblasts (HDFs) were cultured on tissue culture plastics, poly(lactic acid) (PLA) discs with regular open structures, or spherical poly(methyl methacrylate) (PMMA) MSs, respectively. Notably, HDFs exhibited flattened spindle shapes when adhered to solid surfaces, and complex 3D structures when migrating into the structured voids of PLA discs or interstitial spaces between aggregated PMMA MSs, showcasing coordinated colonization of porous scaffolds. Empirical investigations led to power law models simulating density-dependent cell growth on solid surfaces or voids. Concurrently, a modified diffusion model was applied to simulate oxygen diffusion within tissues cultured on solid surfaces or porous structures. These mathematical models were subsequently combined to explore the influences of initial cell seeding density, culture duration, and oxygen diffusion on MT cultivation and assembly. The findings underscored the intricate interplay of factors influencing MT design for tissue assembly. The integrated approach provides insights into mechanistic aspects, informing bioprocess design for manufacturing MTs and 3D tissues in DE. Full article

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23 pages, 7594 KiB

Open AccessReview

Tough Hydrogels with Different Toughening Mechanisms and Applications

by Zhengyu Xu, Yanru Chen, Yi Cao and Bin Xue

Int. J. Mol. Sci. 2024, 25(5), 2675; https://doi.org/10.3390/ijms25052675 - 26 Feb 2024

Cited by 7 | Viewed by 3831

Abstract

Load-bearing biological tissues, such as cartilage and muscles, exhibit several crucial properties, including high elasticity, strength, and recoverability. These characteristics enable these tissues to endure significant mechanical stresses and swiftly recover after deformation, contributing to their exceptional durability and functionality. In contrast, while [...] Read more.

Load-bearing biological tissues, such as cartilage and muscles, exhibit several crucial properties, including high elasticity, strength, and recoverability. These characteristics enable these tissues to endure significant mechanical stresses and swiftly recover after deformation, contributing to their exceptional durability and functionality. In contrast, while hydrogels are highly biocompatible and hold promise as synthetic biomaterials, their inherent network structure often limits their ability to simultaneously possess a diverse range of superior mechanical properties. As a result, the applications of hydrogels are significantly constrained. This article delves into the design mechanisms and mechanical properties of various tough hydrogels and investigates their applications in tissue engineering, flexible electronics, and other fields. The objective is to provide insights into the fabrication and application of hydrogels with combined high strength, stretchability, toughness, and fast recovery as well as their future development directions and challenges. Full article

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19 pages, 7960 KiB

Open AccessArticle

Obtaining Polyvinylpyrrolidone Fibers Using the Electroforming Method with the Inclusion of Microcrystalline High-Temperature Phosphates

by Marina Vladimirovna Papezhuk, Sergei Nikolaevich Ivanin, Roman Pavlovich Yakupov, Vladimir Yurievich Buz’ko, Igor Vladimirovich Sukhno, Anna Nikolaevna Gneush and Iliya Sergeevich Petriev

Int. J. Mol. Sci. 2024, 25(4), 2298; https://doi.org/10.3390/ijms25042298 - 15 Feb 2024

Cited by 1 | Viewed by 985

Abstract

The results of the synthesis of microcrystalline calcium phosphates such as hydroxoapatite, pyrophosphate, and tricalcium phosphate are presented herein. The influence of the addition of polyvinylpyrrolidone (PVP) on the phase characteristics of the resulting high-temperature ceramic sample is considered. The X-ray results show [...] Read more.

The results of the synthesis of microcrystalline calcium phosphates such as hydroxoapatite, pyrophosphate, and tricalcium phosphate are presented herein. The influence of the addition of polyvinylpyrrolidone (PVP) on the phase characteristics of the resulting high-temperature ceramic sample is considered. The X-ray results show that hydroxyapatite (HAp) consists of a Ca₅(PO₄)₃(OH) phase, while the sample with the addition of polyvinylpyrrolidone contains β-Ca₃(PO₄)₂ (65.5%) and β-Ca₂P₂O₇ (34.5%) phases calcium phosphates (CPs). IR spectroscopy was used to characterize the compositions of the samples. An important characteristic of the obtained samples is the elemental Ca/P ratio, which was determined via energy-dispersive analysis. The data obtained are consistent with the composition of dental enamel apatites, namely, in the CPs (1.27) and HAp (1.40). SEM was used to study the morphology of the surfaces of hydroxyapatite particles. Polyvinylpyrrolidone polymer fibers were obtained using the electroforming method with the inclusion of CPs in the composition. The fibers were oriented randomly, and nanoscale hydroxyapatite particles were incorporated into the fiber structure. Solubility data of the HAp, CPs, and Fibers in a physiological solution at room temperature and human body temperature were obtained. The solubility of the resulting HAp turned out to be higher than the solubility of the CPs. In turn, the concentration of Ca²⁺ in a physiological solution of PVP composite fibers with the inclusion of CPs was lower than that in powdered CPs. Full article

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11 pages, 2811 KiB

Open AccessArticle

High-Throughput Synthesis of Nanogap-Rich Gold Nanoshells Using Dual-Channel Infusion System

by Yoon-Hee Kim, Hye-Seong Cho, Kwanghee Yoo, Kyeong-Min Ham, Homan Kang, Xuan-Hung Pham and Bong-Hyun Jun

Int. J. Mol. Sci. 2024, 25(3), 1649; https://doi.org/10.3390/ijms25031649 - 29 Jan 2024

Viewed by 1299

Abstract

Gold nanoshells have been actively applied in industries beyond the research stage because of their unique optical properties. Although numerous methods have been reported for gold nanoshell synthesis, the labor-intensive and time-consuming production process is an issue that must be overcome to meet [...] Read more.

Gold nanoshells have been actively applied in industries beyond the research stage because of their unique optical properties. Although numerous methods have been reported for gold nanoshell synthesis, the labor-intensive and time-consuming production process is an issue that must be overcome to meet industrial demands. To resolve this, we report a high-throughput synthesis method for nanogap-rich gold nanoshells based on a core silica support (denoted as SiO₂@Au NS), affording a 50-fold increase in scale by combining it with a dual-channel infusion pump system. By continuously dropping the reactant solution through the pump, nanoshells with closely packed Au nanoparticles were prepared without interparticle aggregation. The thickness of the gold nanoshells was precisely controlled at 2.3–17.2 nm by regulating the volume of the reactant solution added dropwise. Depending on the shell thickness, the plasmonic characteristics of SiO₂@Au NS prepared by the proposed method could be tuned. Moreover, SiO₂@Au NS exhibited surface-enhanced Raman scattering activity comparable to that of gold nanoshells prepared by a previously reported low-throughput method at the same reactant ratio. The results indicate that the proposed high-throughput synthesis method involving the use of a dual-channel infusion system will contribute to improving the productivity of SiO₂@Au NS with tunable plasmonic characteristics. Full article

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24 pages, 6384 KiB

Open AccessArticle

The Influence of Graphene Oxide-Fe₃O₄ Differently Conjugated with 10-Hydroxycampthotecin and a Rotating Magnetic Field on Adenocarcinoma Cells

by Magdalena Jedrzejczak-Silicka, Karolina Szymańska, Ewa Mijowska and Rafał Rakoczy

Int. J. Mol. Sci. 2024, 25(2), 930; https://doi.org/10.3390/ijms25020930 - 11 Jan 2024

Cited by 2 | Viewed by 1466

Abstract

Nanoparticles (e.g., graphene oxide, graphene oxide-Fe₃O₄ nanocomposite or hexagonal boron nitride) loaded with anti-cancer drugs and targeted at cancerous cells allowed researchers to determine the most effective in vitro conditions for anticancer treatment. For this reason, the main propose of [...] Read more.

Nanoparticles (e.g., graphene oxide, graphene oxide-Fe₃O₄ nanocomposite or hexagonal boron nitride) loaded with anti-cancer drugs and targeted at cancerous cells allowed researchers to determine the most effective in vitro conditions for anticancer treatment. For this reason, the main propose of the present study was to determine the effect of graphene oxide (GO) with iron oxide (Fe₃O₄) nanoparticles (GO-Fe₃O₄) covalently (c-GO-Fe₃O₄-HCPT) and non-covalently (nc-GO-Fe₃O₄-HCPT) conjugated with hydroxycamptothecin (HCPT) in the presence of a rotating magnetic field (RMF) on relative cell viability using the MCF-7 breast cancer cell line. The obtained GO-Fe₃O₄ nanocomposites demonstrated the uniform coverage of the graphene flakes with the nanospheres, with the thickness of the flakes estimated as ca. 1.2 nm. The XRD pattern of GO–Fe₃O₄ indicates that the crystal structure of the magnetite remained stable during the functionalization with HCPT that was confirmed with FTIR spectra. After 24 h, approx. 49% and 34% of the anti-cancer drug was released from nc-GO-Fe₃O₄-HCPT and c-GO-Fe₃O₄-HCPT, respectively. The stronger bonds in the c-GO-Fe₃O₄-HCPT resulted in a slower release of a smaller drug amount from the nanocomposite. The combined impact of the novel nanocomposites and a rotating magnetic field on MCF-7 cells was revealed and the efficiency of this novel approach has been confirmed. However, MCF-7 cells were more significantly affected by nc-GO-Fe₃O₄-HCPT. In the present study, it was found that the concentration of nc-GO-Fe₃O₄-HCPT and a RMF has the highest statistically significant influence on MCF-7 cell viability. The obtained novel nanocomposites and rotating magnetic field were found to affect the MCF-7 cells in a dose-dependent manner. The presented results may have potential clinical applications, but still, more in-depth analyses need to be performed. Full article

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17 pages, 781 KiB

Open AccessArticle

Characterization of Poultry Gelatins Prepared by a Biotechnological Method for Targeted Changes at the Molecular Level

by Aneta Prokopová, Pavel Mokrejš, Robert Gál, Jana Pavlačková and Anna Hurajová

Int. J. Mol. Sci. 2024, 25(2), 916; https://doi.org/10.3390/ijms25020916 - 11 Jan 2024

Cited by 1 | Viewed by 1446

Abstract

Chicken collagen is a promising raw material source for the production gelatins and hydrolysates. These can be prepared biotechnologically using proteolytic enzymes. By choosing the appropriate process conditions, such changes can be achieved at the molecular level of collagen, making it possible to [...] Read more.

Chicken collagen is a promising raw material source for the production gelatins and hydrolysates. These can be prepared biotechnologically using proteolytic enzymes. By choosing the appropriate process conditions, such changes can be achieved at the molecular level of collagen, making it possible to prepare gelatins with targeted properties for advanced cosmetic, pharmaceutical, medical, or food applications. The present research aims to investigate model samples of chicken gelatins, focusing on: (i) antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azinobis-3-etylbenzotiazolin-6-sulfonic acid (ABTS); (ii) the distribution of molecular weights via gel permeation chromatography with refractometric detection (GPC-RID); (iii) functional groups and the configuration of polypeptide chains related to molecular-level properties using Fourier transform infrared spectroscopy (FTIR); (iv) the microbiological populations on sabouraud dextrose agar (SDA), plate count agar (PCA), tryptic soy agar (TSA), and violet red bile lactose (VRBL) using the matrix-assisted laser desorption ionization (MALDI) method. Antioxidant activity towards ABTS radicals was more than 80%; activity towards DPPH radicals was more than 69%. The molecular weights of all gelatin samples showed typical α-, β-, and γ-chains. FTIR analysis confirmed that chicken gelatins all contain typical vibrational regions for collagen cleavage products, Amides A and B, and Amides I, II, and III, at characteristic wavenumbers. A microbiological analysis of the prepared samples showed no undesirable bacteria that would limit advanced applications of the prepared products. Chicken gelatins represent a promising alternative to products made from standard collagen tissues of terrestrial animals. Full article

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12 pages, 1323 KiB

Open AccessArticle

Effect of Solute on Interfacial Properties and Micelle Structure of Dodecylbenzenesulfonate (DBS): Experimental and Molecular Dynamics Studies

by Huang-Chin Hung and Gina S. Shreve

Int. J. Mol. Sci. 2024, 25(1), 678; https://doi.org/10.3390/ijms25010678 - 4 Jan 2024

Viewed by 1342

Abstract

A combined experimental and molecular dynamic simulation approach was used to examine the structure and interfacial properties of solute-saturated micelles. The properties of dodecylbenzenesulfonate (DBS) micelles were examined in dodecane and benzene hydrocarbon systems. Pyrene fluorescence was used to determine the aggregation number [...] Read more.

A combined experimental and molecular dynamic simulation approach was used to examine the structure and interfacial properties of solute-saturated micelles. The properties of dodecylbenzenesulfonate (DBS) micelles were examined in dodecane and benzene hydrocarbon systems. Pyrene fluorescence was used to determine the aggregation number of surfactant monomers in the micelle systems. Molecular dynamic (MD) simulations using energy minimization applying the CHARMm force field with the TIP3P model for water. Comparison of the DBS/benzene and DBS/Dodecane micelles equilibrium structures via radial distribution function (RDF) and probability distribution function (PDF) analysis indicates that the area per head group for the DBS/Benzene micelle interface is significantly larger than that of the DBS/Dodecane at the interface. It was also determined that benzene molecules can move freely within the micelle while dodecane is strictly confined in the core of the micelle. The increased interfacial area per monomer caused by the insertion of benzene also reduces the effectiveness of the surfactant, which has implications for use in various environmental applications. However, the DBS/benzene micelle can solubilize many more hydrocarbon molecules in one micelle with less surfactant monomer (i.e., lower aggregation number) per micelle due to the increased available packing positions within the micelle. This, in turn, increases the efficiency of the surfactant in real-world applications which is consistent with previous laboratory results. Understanding the differing solubilization characteristics of surfactants against various classes of hydrocarbons in single solute systems is a necessary step to beginning to understand their solubilization properties in the mixed waste systems prevalent in most surfactant enhanced remediation (SEAR) strategies. Full article

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2023

Jump to: 2024, 2022, 2021, 2020, 2019

23 pages, 2450 KiB

Open AccessReview

Low-Temperature Plasma Techniques in Biomedical Applications and Therapeutics: An Overview

by Chandrima Karthik, Sarath Chand Sarngadharan and Vinoy Thomas

Int. J. Mol. Sci. 2024, 25(1), 524; https://doi.org/10.3390/ijms25010524 - 30 Dec 2023

Cited by 7 | Viewed by 3077

Abstract

Plasma, the fourth fundamental state of matter, comprises charged species and electrons, and it is a fascinating medium that is spread over the entire visible universe. In addition to that, plasma can be generated artificially under appropriate laboratory techniques. Artificially generated thermal or [...] Read more.

Plasma, the fourth fundamental state of matter, comprises charged species and electrons, and it is a fascinating medium that is spread over the entire visible universe. In addition to that, plasma can be generated artificially under appropriate laboratory techniques. Artificially generated thermal or hot plasma has applications in heavy and electronic industries; however, the non-thermal (cold atmospheric or low temperature) plasma finds its applications mainly in biomedicals and therapeutics. One of the important characteristics of LTP is that the constituent particles in the plasma stream can often maintain an overall temperature of nearly room temperature, even though the thermal parameters of the free electrons go up to 1 to 10 keV. The presence of reactive chemical species at ambient temperature and atmospheric pressure makes LTP a bio-tolerant tool in biomedical applications with many advantages over conventional techniques. This review presents some of the important biomedical applications of cold-atmospheric plasma (CAP) or low-temperature plasma (LTP) in modern medicine, showcasing its effect in antimicrobial therapy, cancer treatment, drug/gene delivery, tissue engineering, implant modifications, interaction with biomolecules, etc., and overviews some present challenges in the field of plasma medicine. Full article

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14 pages, 5149 KiB

Open AccessArticle

Effects of Argon Gas Plasma Treatment on Biocompatibility of Nanostructured Titanium

by Rina Hayashi, Seiji Takao, Satoshi Komasa, Tohru Sekino, Tetsuji Kusumoto and Kenji Maekawa

Int. J. Mol. Sci. 2024, 25(1), 149; https://doi.org/10.3390/ijms25010149 - 21 Dec 2023

Cited by 4 | Viewed by 1488

Abstract

In this study, we applied argon plasma treatment to titanium surfaces with nanostructures deposited by concentrated alkali treatment and investigated the effects on the surface of the material and the tissue surrounding an implant site. The results showed that the treatment with argon [...] Read more.

In this study, we applied argon plasma treatment to titanium surfaces with nanostructures deposited by concentrated alkali treatment and investigated the effects on the surface of the material and the tissue surrounding an implant site. The results showed that the treatment with argon plasma removed carbon contaminants and increased the surface energy of the material while the nanoscale network structure deposited on the titanium surface remained in place. Reactive oxygen species reduced the oxidative stress of bone marrow cells on the treated titanium surface, creating a favorable environment for cell proliferation. Good results were observed in vitro evaluations using rat bone marrow cells. The group treated with argon plasma exhibited the highest apatite formation in experiments using simulated body fluids. The results of in vivo evaluation using rat femurs revealed that the treatment improved the amount of new bone formation around an implant. Thus, the results demonstrate that argon plasma treatment enhances the ability of nanostructured titanium surfaces to induce hard tissue differentiation and supports new bone formation around an implant site. Full article

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15 pages, 2081 KiB

Open AccessArticle

A Direct Comparison of Peptide Drug Delivery Systems Based on the Use of Hybrid Calcium Phosphate/Chitosan Nanoparticles versus Unmixed Calcium Phosphate or Chitosan Nanoparticles In Vitro and In Vivo

by Ekaterina Popova, Victoria Tikhomirova, Olga Beznos, Natalia Chesnokova, Yuri Grigoriev, Michael Taliansky and Olga Kost

Int. J. Mol. Sci. 2023, 24(21), 15532; https://doi.org/10.3390/ijms242115532 - 24 Oct 2023

Cited by 2 | Viewed by 1522

Abstract

Nanocarriers provide a number of undeniable advantages that could improve the bioavailability of active agents for human, animal, and plant cells. In this study, we compared hybrid nanoparticles (HNPs) consisting of a calcium phosphate core coated with chitosan with unmixed calcium phosphate (CaP) [...] Read more.

Nanocarriers provide a number of undeniable advantages that could improve the bioavailability of active agents for human, animal, and plant cells. In this study, we compared hybrid nanoparticles (HNPs) consisting of a calcium phosphate core coated with chitosan with unmixed calcium phosphate (CaP) and chitosan nanoparticles (CSNPs) as carriers of a model substrate, enalaprilat. This tripeptide analog is an inhibitor of angiotensin-converting enzyme and was chosen by its ability to lower intraocular pressure (IOP). In particular, we evaluated the physicochemical characteristics of the particles using dynamic light scattering (DLS) and scanning electron microscopy (SEM) and analyzed their ability to incorporate and release enalaprilat. HNPs exhibited the highest drug loading capacity and both HNPs and CSNPs demonstrated slow drug release. The comparison of the physiological effects of enalaprilat-loaded CaP particles, HNPs, and CSNPs in terms of their impact on IOP in rabbits revealed a clear advantage of hybrid nanoparticles over both inorganic and chitosan nanoparticles. These results could have important mechanistic implications for developing nano-based delivery systems for other medical, veterinary, and agricultural applications. Full article

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12 pages, 2190 KiB

Open AccessArticle

Dopamine-Coated Carbon Nanodots: A Supramolecular Approach to Polydopamine Composite

by Angelo Nicosia, Placido Mineo, Norberto Micali and Valentina Villari

Int. J. Mol. Sci. 2023, 24(20), 15384; https://doi.org/10.3390/ijms242015384 - 20 Oct 2023

Viewed by 1552

Abstract

The development of biocompatible composites constituted by polydopamine and fluorescent carbon dots represents a promising way of exploiting the extraordinary adhesive properties of polydopamine for multi-purpose technologies. Here, a supramolecular complex is realized by the assembly of dopamine on the carbon dots surface, [...] Read more.

The development of biocompatible composites constituted by polydopamine and fluorescent carbon dots represents a promising way of exploiting the extraordinary adhesive properties of polydopamine for multi-purpose technologies. Here, a supramolecular complex is realized by the assembly of dopamine on the carbon dots surface, and the optical and structural properties are investigated by means of different spectroscopic techniques, from time-resolved fluorescence to Raman and NMR spectroscopies. The results suggest that the catechol unit of dopamine plays the main role in the formation of the supramolecular complex, in which carbon nanodot fluorescence emission is quenched by a photoinduced electron transfer process. The interaction with the nanodots’ basic surface sites promotes the oxidation of dopamine and drives to its oligomerization/polymerization on the nanodot surface. Full article

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14 pages, 5454 KiB

Open AccessArticle

Ni-Based Hydrotalcite (HT)-Derived Cu Catalysts for Catalytic Conversion of Bioethanol to Butanol

by Yan Xiao, Jie Li, Yuan Tan, Xingkun Chen, Fenghua Bai, Wenhao Luo and Yunjie Ding

Int. J. Mol. Sci. 2023, 24(19), 14859; https://doi.org/10.3390/ijms241914859 - 3 Oct 2023

Cited by 1 | Viewed by 1502

Abstract

Catalytic conversion of biomass-derived ethanol into n-butanol through Guerbet coupling reaction has become one of the key reactions in biomass valorization, thus attracting significant attention recently. Herein, a series of supported Cu catalysts derived from Ni-based hydrotalcite (HT) were prepared and performed in [...] Read more.

Catalytic conversion of biomass-derived ethanol into n-butanol through Guerbet coupling reaction has become one of the key reactions in biomass valorization, thus attracting significant attention recently. Herein, a series of supported Cu catalysts derived from Ni-based hydrotalcite (HT) were prepared and performed in the continuous catalytic conversion of ethanol into butanol. Among the prepared catalysts, Cu/NiAlO_x shows the best performance in terms of butanol selectivity and catalyst stability, with a sustained ethanol conversion of ~35% and butanol selectivity of 25% in a time-on-stream (TOS) of 110 h at 280 °C. While for the Cu/NiFeO_x and Cu/NiCoO_x, obvious catalyst deactivation and/or low butanol selectivity were obtained. Extensive characterization studies of the fresh and spent catalysts, i.e., X-ray diffraction (XRD), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and Hydrogen temperature-programmed reduction (H₂-TPR), reveal that the catalysts’ deactivation is mainly caused by the support deconstruction during catalysis, which is highly dependent on the reducibility. Additionally, an appropriate acid–base property is pivotal for enhancing the product selectivity, which is beneficial for the key process of aldol-condensation to produce butanol. Full article

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12 pages, 3503 KiB

Open AccessArticle

Investigating the Effect of Surface Hydrophilicity on the Destiny of PLGA-Poloxamer Nanoparticles in an In Vivo Animal Model

by Teresa Silvestri, Lucia Grumetto, Ilaria Neri, Maria De Falco, Sossio Fabio Graziano, Sara Damiano, Daniela Giaquinto, Lucianna Maruccio, Paolo de Girolamo, Fabrizio Villapiano, Roberto Ciarcia, Laura Mayol and Marco Biondi

Int. J. Mol. Sci. 2023, 24(19), 14523; https://doi.org/10.3390/ijms241914523 - 25 Sep 2023

Cited by 3 | Viewed by 1647

Abstract

This study aimed to examine the impact of different surface properties of poly(lactic-co-glycolic) acid (PLGA) nanoparticles (P NPs) and PLGA-Poloxamer nanoparticles (PP NPs) on their in vivo biodistribution. For this purpose, NPs were formulated via nanoprecipitation and loaded with diphenylhexatriene (DPH), a fluorescent [...] Read more.

This study aimed to examine the impact of different surface properties of poly(lactic-co-glycolic) acid (PLGA) nanoparticles (P NPs) and PLGA-Poloxamer nanoparticles (PP NPs) on their in vivo biodistribution. For this purpose, NPs were formulated via nanoprecipitation and loaded with diphenylhexatriene (DPH), a fluorescent dye. The obtained NPs underwent comprehensive characterization, encompassing their morphology, technological attributes, DPH release rate, and thermodynamic properties. The produced NPs were then administered to wild-type mice via intraperitoneal injection, and, at scheduled time intervals, the animals were euthanized. Blood samples, as well as the liver, lungs, and kidneys, were extracted for histological examination and biodistribution analysis. The findings of this investigation revealed that the presence of poloxamers led to smaller NP sizes and induced partial crystallinity in the NPs. The biodistribution and histological results from in vivo experiments evidenced that both, P and PP NPs, exhibited comparable concentrations in the bloodstream, while P NPs could not be detected in the other organs examined. Conversely, PP NPs were primarily sequestered by the lungs and, to a lesser extent, by the kidneys. Future research endeavors will focus on investigating the behavior of drug-loaded NPs in pathological animal models. Full article

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13 pages, 4325 KiB

Open AccessArticle

Enhanced Antibacterial Ability of Electrospun PCL Scaffolds Incorporating ZnO Nanowires

by Jingjing Tian, Thomas E. Paterson, Jingjia Zhang, Yingxing Li, Han Ouyang, Ilida Ortega Asencio, Paul V. Hatton, Yu Zhao and Zhou Li

Int. J. Mol. Sci. 2023, 24(19), 14420; https://doi.org/10.3390/ijms241914420 - 22 Sep 2023

Cited by 6 | Viewed by 1710

Abstract

The infection of implanted biomaterial scaffolds presents a major challenge. Existing therapeutic solutions, such as antibiotic treatment and silver nanoparticle-containing scaffolds are becoming increasingly impractical because of the growth of antibiotic resistance and the toxicity of silver nanoparticles. We present here a novel [...] Read more.

The infection of implanted biomaterial scaffolds presents a major challenge. Existing therapeutic solutions, such as antibiotic treatment and silver nanoparticle-containing scaffolds are becoming increasingly impractical because of the growth of antibiotic resistance and the toxicity of silver nanoparticles. We present here a novel concept to overcome these limitations, an electrospun polycaprolactone (PCL) scaffold functionalised with zinc oxide nanowires (ZnO NWs). This study assessed the antibacterial capabilities and biocompatibility of PCL/ZnO scaffolds. The fabricated scaffolds were characterised by SEM and EDX, which showed that the ZnO NWs were successfully incorporated and distributed in the electrospun PCL scaffolds. The antibacterial properties were investigated by co-culturing PCL/ZnO scaffolds with Staphylococcus aureus. Bacterial colonisation was reduced to 51.3% compared to a PCL-only scaffold. The biocompatibility of the PCL/ZnO scaffolds was assessed by culturing them with HaCaT cells. The PCL scaffolds exhibited no changes in cell metabolic activity with the addition of the ZnO nanowires. The antibacterial and biocompatibility properties make PCL/ZnO a good choice for implanted scaffolds, and this work lays a foundation for ZnO NWs-infused PCL scaffolds in the potential clinical application of tissue engineering. Full article

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11 pages, 14561 KiB

Open AccessArticle

The Anti-Caries Effects of a Novel Peptide on Dentine Caries: An In Vitro Study

by Olivia Lili Zhang, John Yun Niu, Ollie Yiru Yu, Iris Xiaoxue Yin, May Lei Mei and Chun Hung Chu

Int. J. Mol. Sci. 2023, 24(18), 14076; https://doi.org/10.3390/ijms241814076 - 14 Sep 2023

Cited by 4 | Viewed by 1286

Abstract

This study aimed to investigate the antibiofilm and remineralising effects of peptide GAPI on artificial dentin caries. After creating artificial carious lesions, eighty dentine blocks were randomly assigned for treatment twice daily with GAPI (GAPI group) or deionised water (control group). Both groups [...] Read more.

This study aimed to investigate the antibiofilm and remineralising effects of peptide GAPI on artificial dentin caries. After creating artificial carious lesions, eighty dentine blocks were randomly assigned for treatment twice daily with GAPI (GAPI group) or deionised water (control group). Both groups underwent a 7-day biochemical cycle. Scanning electron microscopy (SEM) showed S. mutans with damaged structures that partially covered the dentine in the GAPI group. The dead–live ratios for the GAPI and control groups were 0.77 ± 0.13 and 0.37 ± 0.09 (p < 0.001). The log colony-forming units for the GAPI and control groups were 7.45 ± 0.32 and 8.74 ± 0.50 (p < 0.001), respectively. The lesion depths for the GAPI and control groups were 151 ± 18 µm and 214 ± 15 µm (p < 0.001), respectively. The mineral losses for the GAPI and control groups were 0.91 ± 0.07 gHAcm⁻³ and 1.01 ± 0.07 gHAcm⁻³ (p = 0.01), respectively. The hydrogen-to-amide I ratios for the GAPI and control groups were 2.92 ± 0.82 and 1.83 ± 0.73 (p = 0.014), respectively. SEM micrographs revealed fewer exposed dentine collagen fibres in the GAPI group compared to those in the control group. Furthermore, X-ray diffraction (XRD) patterns indicated that the hydroxyapatite in the GAPI group was more crystallised than that in the control group. This study demonstrated GAPI’s antibiofilm and remineralising effects on artificial dentin caries. Full article

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25 pages, 7921 KiB

Open AccessReview

Nano-Enabled Antivirals for Overcoming Antibody Escaped Mutations Based SARS-CoV-2 Waves

by Aminur Rahman, Kumar Jyotirmoy Roy, Gautam Kumar Deb, Taehyeong Ha, Saifur Rahman, Mst. Khudishta Aktar, Md. Isahak Ali, Md. Abdul Kafi and Jeong-Woo Choi

Int. J. Mol. Sci. 2023, 24(17), 13130; https://doi.org/10.3390/ijms241713130 - 23 Aug 2023

Cited by 1 | Viewed by 2884

Abstract

This review discusses receptor-binding domain (RBD) mutations related to the emergence of various SARS-CoV-2 variants, which have been highlighted as a major cause of repetitive clinical waves of COVID-19. Our perusal of the literature reveals that most variants were able to escape neutralizing [...] Read more.

This review discusses receptor-binding domain (RBD) mutations related to the emergence of various SARS-CoV-2 variants, which have been highlighted as a major cause of repetitive clinical waves of COVID-19. Our perusal of the literature reveals that most variants were able to escape neutralizing antibodies developed after immunization or natural exposure, pointing to the need for a sustainable technological solution to overcome this crisis. This review, therefore, focuses on nanotechnology and the development of antiviral nanomaterials with physical antagonistic features of viral replication checkpoints as such a solution. Our detailed discussion of SARS-CoV-2 replication and pathogenesis highlights four distinct checkpoints, the S protein (ACE2 receptor coupling), the RBD motif (ACE2 receptor coupling), ACE2 coupling, and the S protein cleavage site, as targets for the development of nano-enabled solutions that, for example, prevent viral attachment and fusion with the host cell by either blocking viral RBD/spike proteins or cellular ACE2 receptors. As proof of this concept, we highlight applications of several nanomaterials, such as metal and metal oxide nanoparticles, carbon-based nanoparticles, carbon nanotubes, fullerene, carbon dots, quantum dots, polymeric nanoparticles, lipid-based, polymer-based, lipid–polymer hybrid-based, surface-modified nanoparticles that have already been employed to control viral infections. These nanoparticles were developed to inhibit receptor-mediated host–virus attachments and cell fusion, the uncoating of the virus, viral gene expression, protein synthesis, the assembly of progeny viral particles, and the release of the virion. Moreover, nanomaterials have been used as antiviral drug carriers and vaccines, and nano-enabled sensors have already been shown to enable fast, sensitive, and label-free real-time diagnosis of viral infections. Nano-biosensors could, therefore, also be useful in the remote testing and tracking of patients, while nanocarriers probed with target tissue could facilitate the targeted delivery of antiviral drugs to infected cells, tissues, organs, or systems while avoiding unwanted exposure of non-target tissues. Antiviral nanoparticles can also be applied to sanitizers, clothing, facemasks, and other personal protective equipment to minimize horizontal spread. We believe that the nanotechnology-enabled solutions described in this review will enable us to control repeated SAR-CoV-2 waves caused by antibody escape mutations. Full article

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13 pages, 2523 KiB

Open AccessArticle

Blocking Nonspecific Interactions Using Y-Shape Poly(ethylene glycol)

by Zhengyu Xu, Qingtai Li, Yaying Huang, Kaiqiang Guo, Bin Xue, Yi Cao and Yiran Li

Int. J. Mol. Sci. 2023, 24(15), 12414; https://doi.org/10.3390/ijms241512414 - 4 Aug 2023

Cited by 1 | Viewed by 1907

Abstract

Nonspecific interactions play a significant role in physiological activities, surface chemical modification, and artificial adhesives. However, nonspecificity sometimes causes sticky problems, including surface fouling, decreased target specificity, and artifacts in single-molecule measurements. Adjusting the liquid pH, using protein-blocking additives, adding nonionic surfactants, or [...] Read more.

Nonspecific interactions play a significant role in physiological activities, surface chemical modification, and artificial adhesives. However, nonspecificity sometimes causes sticky problems, including surface fouling, decreased target specificity, and artifacts in single-molecule measurements. Adjusting the liquid pH, using protein-blocking additives, adding nonionic surfactants, or increasing the salt concentration are common methods to minimize nonspecific binding to achieve high-quality data. Here, we report that grafting heteromorphic polyethylene glycol (Y-shape PEG) with two inert terminates could noticeably decrease nonspecific binding. As a proof-of-concept, we performed single-molecule force spectroscopy and fluorescence staining imaging experiments to verify the feasibility of Y-shape PEG in blocking nonspecific interactions. Our results indicate that Y-shape PEG could serve as a prominent and efficient candidate to minimize nonspecificity for scientific and biomedical applications. Full article

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11 pages, 4824 KiB

Open AccessCommunication

Preparation and Testing of a Palladium-Decorated Nitrogen-Doped Carbon Foam Catalyst for the Hydrogenation of Benzophenone

by Ádám Prekob, Viktória Hajdu, Zsolt Fejes, Ferenc Kristály, Béla Viskolcz and László Vanyorek

Int. J. Mol. Sci. 2023, 24(15), 12211; https://doi.org/10.3390/ijms241512211 - 30 Jul 2023

Viewed by 1285

Abstract

Catalytic activity of a palladium catalyst with a porous carbon support was prepared and tested for benzophenone hydrogenation. The selectivity and yields toward the two possible reaction products (benzhydrol and diphenylmethane) can be directed by the applied solvent. It was found that in [...] Read more.

Catalytic activity of a palladium catalyst with a porous carbon support was prepared and tested for benzophenone hydrogenation. The selectivity and yields toward the two possible reaction products (benzhydrol and diphenylmethane) can be directed by the applied solvent. It was found that in isopropanol, the prepared support was selective towards diphenylmethane with high conversion (99% selectivity and 99% benzophenone conversion on 323 K after 240 min). This selectivity might be explained by the presence of the incorporated structural nitrogens in the support. Full article

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13 pages, 9556 KiB

Open AccessArticle

A Density Functional Theory (DFT) Perspective on Optical Absorption of Modified Graphene Interacting with the Main Amino Acids of Spider Silk

by Ali Fransuani Jiménez-González, Juan Manuel Ramírez-de-Arellano and Luis Fernando Magaña Solís

Int. J. Mol. Sci. 2023, 24(15), 12084; https://doi.org/10.3390/ijms241512084 - 28 Jul 2023

Cited by 2 | Viewed by 1440

Abstract

We investigated the possible adsorption of each of the main building blocks of spider silk: alanine, glycine, leucine, and proline. This knowledge could help develop new biocompatible materials and favors the creation of new biosensors. We used ab initio density functional theory methods [...] Read more.

We investigated the possible adsorption of each of the main building blocks of spider silk: alanine, glycine, leucine, and proline. This knowledge could help develop new biocompatible materials and favors the creation of new biosensors. We used ab initio density functional theory methods to study the variations in the optical absorption, reflectivity, and band structure of a modified graphene surface interacting with these four molecules. Four modification cases were considered: graphene with vacancies at 5.55% and fluorine, nitrogen, or oxygen doping, also at 5.55%. We found that, among the cases considered, graphene with vacancies is the best candidate to develop optical biosensors to detect C=O amide and differentiate glycine and leucine from alanine and proline in the visible spectrum region. Finally, from the projected density of states, the main changes occur at deep energies. Thus, all modified graphene’s electronic energy band structure undergoes only tiny changes when interacting with amino acids. Full article

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15 pages, 4514 KiB

Open AccessArticle

Self-Standing Pd-Based Nanostructures for Electrocatalytic CO Oxidation: Do Nanocatalyst Shape and Electrolyte pH Matter?

by Belal Salah, Adewale K. Ipadeola, Aboubakr M. Abdullah, Alaa Ghanem and Kamel Eid

Int. J. Mol. Sci. 2023, 24(14), 11832; https://doi.org/10.3390/ijms241411832 - 23 Jul 2023

Cited by 6 | Viewed by 1533

Abstract

Tailoring the shape of Pd nanocrystals is one of the main ways to enhance catalytic activity; however, the effect of shapes and electrolyte pH on carbon monoxide oxidation (CO_Oxid) is not highlighted enough. This article presents the controlled fabrication of Pd [...] Read more.

Tailoring the shape of Pd nanocrystals is one of the main ways to enhance catalytic activity; however, the effect of shapes and electrolyte pH on carbon monoxide oxidation (CO_Oxid) is not highlighted enough. This article presents the controlled fabrication of Pd nanocrystals in different morphologies, including Pd nanosponge via the ice-cooling reduction of the Pd precursor using NaBH₄ solution and Pd nanocube via ascorbic acid reduction at 25 °C. Both Pd nanosponge and Pd nanocube are self-standing and have a high surface area, uniform distribution, and clean surface. The electrocatalytic CO oxidation activity and durability of the Pd nanocube were significantly superior to those of Pd nanosponge and commercial Pd/C in only acidic (H₂SO₄) medium and the best among the three media, due to the multiple adsorption active sites, uniform distribution, and high surface area of the nanocube structure. However, Pd nanosponge had enhanced CO_Oxid activity and stability in both alkaline (KOH) and neutral (NaHCO₃) electrolytes than Pd nanocube and Pd/C, attributable to its low Pd-Pd interatomic distance and cleaner surface. The self-standing Pd nanosponge and Pd nanocube were more active than Pd/C in all electrolytes. Mainly, the CO_Oxid current density of Pd nanocube in H₂SO₄ (5.92 mA/cm²) was nearly 3.6 times that in KOH (1.63 mA/cm²) and 10.3 times that in NaHCO₃ (0.578 mA/cm²), owing to the greater charge mobility and better electrolyte–electrode interaction, as evidenced by electrochemical impedance spectroscopy (EIS) analysis. Notably, this study confirmed that acidic electrolytes and Pd nanocube are highly preferred for promoting CO_Oxid and may open new avenues for precluding CO poisoning in alcohol-based fuel cells. Full article

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47 pages, 8301 KiB

Open AccessReview

Lignin, the Lignification Process, and Advanced, Lignin-Based Materials

by Maria Balk, Pietro Sofia, Axel T. Neffe and Nicola Tirelli

Int. J. Mol. Sci. 2023, 24(14), 11668; https://doi.org/10.3390/ijms241411668 - 19 Jul 2023

Cited by 28 | Viewed by 10941

Abstract

At a time when environmental considerations are increasingly pushing for the application of circular economy concepts in materials science, lignin stands out as an under-used but promising and environmentally benign building block. This review focuses (A) on understanding what we mean with lignin, [...] Read more.

At a time when environmental considerations are increasingly pushing for the application of circular economy concepts in materials science, lignin stands out as an under-used but promising and environmentally benign building block. This review focuses (A) on understanding what we mean with lignin, i.e., where it can be found and how it is produced in plants, devoting particular attention to the identity of lignols (including ferulates that are instrumental for integrating lignin with cell wall polysaccharides) and to the details of their coupling reactions and (B) on providing an overview how lignin can actually be employed as a component of materials in healthcare and energy applications, finally paying specific attention to the use of lignin in the development of organic shape-memory materials. Full article

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16 pages, 16370 KiB

Open AccessArticle

Fabrication, Structure, and Properties of Nonwoven Silk Fabrics Prepared with Different Cocoon Layers

by Yun Yeong Choi, Mi Jin Jang, Byung-Dae Park and In Chul Um

Int. J. Mol. Sci. 2023, 24(14), 11485; https://doi.org/10.3390/ijms241411485 - 14 Jul 2023

Cited by 3 | Viewed by 2237

Abstract

In this study, five different nonwoven silk fabrics were fabricated with silk fibers from different cocoon layers, and the effect of the cocoon layer on the structural characteristics and properties of the nonwoven silk fabric was examined. The diameter of the silk fiber [...] Read more.

In this study, five different nonwoven silk fabrics were fabricated with silk fibers from different cocoon layers, and the effect of the cocoon layer on the structural characteristics and properties of the nonwoven silk fabric was examined. The diameter of the silk fiber and thickness of the nonwoven silk fabric decreased from the outer to the inner cocoon layer. More amino acids with higher hydrophilicity (serine, aspartic acid, and glutamic acid) and lower hydrophilicity (glycine and alanine) were observed in the outer layers. From the outer to the inner layer, the overall crystallinity and contact angle of the nonwoven silk fabric increased, whereas its yellowness index, moisture retention, and mechanical properties decreased. Regardless of the cocoon layer at which the fiber was sourced, the thermal stability of fibroin and sericin and good cell viability remained unchanged. The results of this study indicate that the properties of nonwoven silk fabric can be controlled by choosing silk fibers from the appropriate cocoon layers. Moreover, the findings in this study will increase the applicability of nonwoven silk fabric in the biomedical and cosmetic fields, which require specific properties for industrialization. Full article

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15 pages, 3858 KiB

Open AccessArticle

Functionalized Ordered Mesoporous MCM-48 Silica: Synthesis, Characterization and Adsorbent for CO₂ Capture

by Silvana Borcănescu, Alexandru Popa, Orsina Verdeș and Mariana Suba

Int. J. Mol. Sci. 2023, 24(12), 10345; https://doi.org/10.3390/ijms241210345 - 19 Jun 2023

Cited by 9 | Viewed by 2574

Abstract

The ordered mesoporous silica MCM-48 with cubic Ia3d structure was synthesized using the cationic surfactant hexadecyltrimethylammonium bromide (CTAB) as a template agent and tetraethylorthosilicate (TEOS) as a silica source. The obtained material was first functionalized with (3-glycidyloxypropyl)trimethoxysilane (KH560); further, two types of amination [...] Read more.

The ordered mesoporous silica MCM-48 with cubic Ia3d structure was synthesized using the cationic surfactant hexadecyltrimethylammonium bromide (CTAB) as a template agent and tetraethylorthosilicate (TEOS) as a silica source. The obtained material was first functionalized with (3-glycidyloxypropyl)trimethoxysilane (KH560); further, two types of amination reagents were used: ethylene diamine (N2) and diethylene triamine (N3). The modified amino-functionalized materials were characterized by powder X-ray diffraction (XRD) at low angles, infrared spectroscopy (FT-IR) and nitrogen adsorption–desorption experiments at 77 K. Characterization from a structural point of view reveals that the ordered MCM-48 mesoporous silica has a highly ordered structure and a large surface area (1466.059 m²/g) and pore volume (0.802 cm³/g). The amino-functionalized MCM-48 molecular sieves were tested for CO₂ adsorption–desorption properties at different temperatures using thermal program desorption (TPD). Promising results for CO₂ adsorption capacities were achieved for MCM-48 sil KH560-N3 at 30 °C. At 30 °C, the MCM-48 sil KH560-N3 sample has an adsorption capacity of 3.17 mmol CO₂/g SiO₂, and an efficiency of amino groups of 0.58 mmol CO₂/mmolNH₂. After nine adsorption–desorption cycles, the results suggest that the performance of the MCM-48 sil KH N2 and MCM-48 sil KH N3 adsorbents is relatively stable, presenting a low decrease in the adsorption capacity. The results reported in this paper for the investigated amino-functionalized molecular sieves as absorbents for CO₂ can be considered as promising. Full article

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13 pages, 2434 KiB

Open AccessArticle

A Green Synthesis of CoFe₂O₄ Decorated ZIF-8 Composite for Electrochemical Oxygen Evolution

by Atanu Panda, Hang-Kyu Cho and Hansang Kim

Int. J. Mol. Sci. 2023, 24(11), 9585; https://doi.org/10.3390/ijms24119585 - 31 May 2023

Cited by 7 | Viewed by 1999

Abstract

Low-cost, sustainable hydrogen production requires noble metal-free electrocatalysts for water splitting. In this study, we prepared zeolitic imidazolate frameworks (ZIF) decorated with CoFe₂O₄ spinel nanoparticles as active catalysts for oxygen evolution reaction (OER). The CoFe₂O₄ nanoparticles were [...] Read more.

Low-cost, sustainable hydrogen production requires noble metal-free electrocatalysts for water splitting. In this study, we prepared zeolitic imidazolate frameworks (ZIF) decorated with CoFe₂O₄ spinel nanoparticles as active catalysts for oxygen evolution reaction (OER). The CoFe₂O₄ nanoparticles were synthesized by converting agricultural bio-waste (potato peel extract) into economically valuable electrode materials. The biogenic CoFe₂O₄ composite showed an overpotential of 370 mV at a current density of 10 mA cm⁻² and a low Tafel slope of 283 mV dec⁻¹, whereas the ZIF@CoFe₂O₄ composite prepared using an in situ hydrothermal method showed an overpotential of 105 mV at 10 mA cm⁻² and a low Tafel slope of 43 mV dec⁻¹ in a 1 M KOH medium. The results demonstrated an exciting prospect of high-performance noble metal-free electrocatalysts for low-cost, high-efficiency, and sustainable hydrogen production. Full article

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20 pages, 3009 KiB

Open AccessArticle

Investigating the Theranostic Potential of Graphene Quantum Dots in Alzheimer’s Disease

by Max Walton-Raaby, Riley Woods and Subha Kalyaanamoorthy

Int. J. Mol. Sci. 2023, 24(11), 9476; https://doi.org/10.3390/ijms24119476 - 30 May 2023

Cited by 4 | Viewed by 3296

Abstract

Alzheimer’s disease (AD) is one of the leading causes of death worldwide, with no definitive diagnosis or known cure. The aggregation of Tau protein into neurofibrillary tangles (NFTs), which contain straight filaments (SFs) and paired helical filaments (PHFs), is a major hallmark of [...] Read more.

Alzheimer’s disease (AD) is one of the leading causes of death worldwide, with no definitive diagnosis or known cure. The aggregation of Tau protein into neurofibrillary tangles (NFTs), which contain straight filaments (SFs) and paired helical filaments (PHFs), is a major hallmark of AD. Graphene quantum dots (GQDs) are a type of nanomaterial that combat many of the small-molecule therapeutic challenges in AD and have shown promise in similar pathologies. In this study, two sizes of GQDs, GQD7 and GQD28, were docked to various forms of Tau monomers, SFs, and PHFs. From the favorable docked poses, we simulated each system for at least 300 ns and calculated the free energies of binding. We observed a clear preference for GQD28 in the PHF6 (³⁰⁶VQIVYK³¹¹) pathological hexapeptide region of monomeric Tau, while GQD7 targeted both the PHF6 and PHF6* (²⁷⁵VQIINK²⁸⁰) pathological hexapeptide regions. In SFs, GQD28 had a high affinity for a binding site that is available in AD but not in other common tauopathies, while GQD7 behaved promiscuously. In PHFs, GQD28 interacted strongly near the protofibril interface at the putative disaggregation site for epigallocatechin-3-gallate, and GQD7 largely interacted with PHF6. Our analyses revealed several key GQD binding sites that may be used for detecting, preventing, and disassembling the Tau aggregates in AD. Full article

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15 pages, 3164 KiB

Open AccessArticle

Study of the Electronic Interaction between NiO and Short Polythiophene Chains towards Solar Photon Harvesting

by Guillermo Carbajal-Franco, María Fernanda Márquez-Quintana, Hugo Rojas-Chávez and Alan Miralrio

Int. J. Mol. Sci. 2023, 24(11), 9109; https://doi.org/10.3390/ijms24119109 - 23 May 2023

Viewed by 1630

Abstract

The sustainable production of energy is a field of interest to which a new requirement is now imposed: the need to be respectful of the environment. New materials and techniques are being developed, but environmental concerns impose the necessity of keeping research active [...] Read more.

The sustainable production of energy is a field of interest to which a new requirement is now imposed: the need to be respectful of the environment. New materials and techniques are being developed, but environmental concerns impose the necessity of keeping research active towards the development of green energy. For this reason, we present the study of short polythiophene (PTh) chains (three and five monomers) and their interaction with nickel oxide, looking for properties related to solar photon harvesting in order to produce electricity. The models of the molecules were developed, and the calculations were performed with an M11-L meta-GGA functional, specially developed for electronic structure calculations. The theoretical explorations demonstrated that the geometry of the PTh molecules suffer little distortion when interacting with the NiO molecule. The calculated value of E_g lies between 2.500 and 0.412 eV for a three-ring PTh chain and between 1.944 and 0.556 eV for a five-ring PTh chain. The chemical parameters indicated that, depending on the geometry of the system, the chemical potential varies from 81.27 to 102.38 kcal/mol and the highest amount of electronic charge varies from −2.94 to 21.56 a.u. for three-monomer systems. For five-monomer systems, the values lie within similar ranges as those of the three-monomer systems. The Partial Density of States (PDOS) showed that the valence and conduction electronic bands were composed of states in the NiO and PTh rings, except for a system where there was a non-bonding interaction. Full article

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13 pages, 6148 KiB

Open AccessArticle

Near-Infrared Light-Activated Mesoporous Polydopamine for Temporomandibular Joint Osteoarthritis Combined Photothermal-Chemo Therapy

by Qianli Li, Yi Hou, Pinyin Cao, Ruiye Bi and Songsong Zhu

Int. J. Mol. Sci. 2023, 24(10), 9055; https://doi.org/10.3390/ijms24109055 - 21 May 2023

Cited by 3 | Viewed by 2601

Abstract

The treatments generally employed for temporomandibular joint osteoarthritis (TMJOA) involve physical therapy and chemotherapy, etc., whose therapeutic efficacies are impaired by the side effects and suboptimal stimulus responsiveness. Although the intra-articular drug delivery system (DDS) has shown effectiveness in addressing osteoarthritis, there is [...] Read more.

The treatments generally employed for temporomandibular joint osteoarthritis (TMJOA) involve physical therapy and chemotherapy, etc., whose therapeutic efficacies are impaired by the side effects and suboptimal stimulus responsiveness. Although the intra-articular drug delivery system (DDS) has shown effectiveness in addressing osteoarthritis, there is currently little reported research regarding the use of stimuli-responsive DDS in managing TMJOA. Herein, we prepared a novel near-infrared (NIR) light-sensitive DDS (DS-TD/MPDA) by using mesoporous polydopamine nanospheres (MPDA) as NIR responders and drug carriers; diclofenac sodium (DS) as the anti-inflammatory medication; and 1-tetradecanol (TD) with a phase-inversion temperature of 39 °C as the drug administrator. Upon exposure to 808 nm NIR laser, DS-TD/MPDA could raise the temperature up to the melting point of TD through photothermal conversion, and intelligently trigger DS release. The resultant nanospheres exhibited an excellent photothermal effect and effectively controlled the release of DS through laser irradiation to accommodate the multifunctional therapeutic effect. More importantly, the biological evaluation of DS-TD/MPDA for TMJOA treatment was also performed for the first time. The experiments’ results demonstrated that DS-TD/MPDA displayed a good biocompatibility in vitro and in vivo during metabolism. After injection into the TMJ of rats afflicted with TMJOA induced by unilateral anterior crossbite for 14 days, DS-TD/MPDA could alleviate the deterioration of TMJ cartilage, thus ameliorating osteoarthritis. Therefore, DS-TD/MPDA could be a promising candidate for photothermal-chemotherapy for TMJOA. Full article

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19 pages, 4586 KiB

Open AccessArticle

Ru(II) Oxygen Sensors for Co(III) Complexes and Amphotericin B Antifungal Activity Detection by Phosphorescence Optical Respirometry

by Katarzyna Turecka, Agnieszka Chylewska, Aleksandra M. Dąbrowska, Rafał Hałasa, Czesława Orlewska and Krzysztof Waleron

Int. J. Mol. Sci. 2023, 24(10), 8744; https://doi.org/10.3390/ijms24108744 - 14 May 2023

Cited by 4 | Viewed by 1930

Abstract

The measurement of oxygen consumption is an important element in the understanding of an organism’s metabolic state. Oxygen is also a phosphorescence quencher, which allows the evaluation of phosphorescence emitted by oxygen sensors. Two Ru(II)-based oxygen-sensitive sensors were used to study the effect [...] Read more.

The measurement of oxygen consumption is an important element in the understanding of an organism’s metabolic state. Oxygen is also a phosphorescence quencher, which allows the evaluation of phosphorescence emitted by oxygen sensors. Two Ru(II)-based oxygen-sensitive sensors were used to study the effect of chemical compounds [(1) = [CoCl₂(dap)₂]Cl, and (2) = [CoCl₂(en)₂]Cl (AmB = amphotericin B) against reference and clinical strains of Candida albicans. The tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] chloride ([Ru(DPP)₃]Cl₂) (Box) adsorbed onto the Davisil^TM silica gel was embedded in the silicone rubber Lactite NuvaSil^® 5091 and the coating on the bottom of 96-well plates. The water-soluble oxygen sensor (BsOx = tris-[(4,7-diphenyl-1,10-phenanthrolinedisulphonic acid disodium)ruthenium(II)] chloride ‘x’ hydrate = {Ru[DPP(SO₃Na)₂]₃}Cl₂ = water molecules were omitted in the BsOx formula) was synthesized and characterized by RP-UHPLC, LCMS, MALDI, elemental analysis, ATR, UV-Vis, ¹H NMR, and TG/IR techniques. The microbiological studies were performed in the environment of RPMI broth and blood serum. Both Ru(II)-based sensors turned out to be useful in the study of the activity of Co(III) complexes and the commercial antifungal drug amphotericin B. In addition, a new activity of the oxygen sensor, the soluble Ru(II) complex BsOx, was demonstrated, which is a mixture with amphotericin B that caused a significant increase in its antifungal activity. Thus, it is also possible to demonstrate the synergistic effect of compounds active against the microorganisms under study. Full article

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21 pages, 2286 KiB

Open AccessReview

Deep Eutectic Solvents Comprising Organic Acids and Their Application in (Bio)Medicine

by Tomasz Swebocki, Alexandre Barras, Amar Abderrahmani, Kamel Haddadi and Rabah Boukherroub

Int. J. Mol. Sci. 2023, 24(10), 8492; https://doi.org/10.3390/ijms24108492 - 9 May 2023

Cited by 13 | Viewed by 4430

Abstract

Over the last years, we observed a significant increase in the number of published studies that focus on the synthesis and characterization of deep eutectic solvents (DESs). These materials are of particular interest mainly due to their physical and chemical stability, low vapor [...] Read more.

Over the last years, we observed a significant increase in the number of published studies that focus on the synthesis and characterization of deep eutectic solvents (DESs). These materials are of particular interest mainly due to their physical and chemical stability, low vapor pressure, ease of synthesis, and the possibility of tailoring their properties through dilution or change of the ratio of parent substances (PS). DESs, considered as one of the greenest families of solvents, are used in many fields, such as organic synthesis, (bio)catalysis, electrochemistry, and (bio)medicine. DESs applications have already been reported in various review articles. However, these reports mainly described these components’ basics and general properties without focusing on the particular, PS-wise, group of DESs. Many DESs investigated for potential (bio)medical applications comprise organic acids. However, due to the different aims of the reported studies, many of these substances have not yet been investigated thoroughly, which makes it challenging for the field to move forward. Herein, we propose distinguishing DESs comprising organic acids (OA-DESs) as a specific group derived from natural deep eutectic solvents (NADESs). This review aims to highlight and compare the applications of OA-DESs as antimicrobial agents and drug delivery enhancers—two essential fields in (bio)medical studies where DESs have already been implemented and proven their potential. From the survey of the literature data, it is evident that OA-DESs represent an excellent type of DESs for specific biomedical applications, owing to their negligible cytotoxicity, fulfilling the rules of green chemistry and being generally effective as drug delivery enhancers and antimicrobial agents. The main focus is on the most intriguing examples and (where possible) application-based comparison of particular groups of OA-DESs. This should highlight the importance of OA-DESs and give valuable clues on the direction the field can take. Full article

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Graphical abstract

11 pages, 3891 KiB

Open AccessArticle

Domain Localization by Graphene Oxide in Supported Lipid Bilayers

by Ryugo Tero, Yoshi Hagiwara and Shun Saito

Int. J. Mol. Sci. 2023, 24(9), 7999; https://doi.org/10.3390/ijms24097999 - 28 Apr 2023

Cited by 3 | Viewed by 1993

Abstract

The gel-phase domains in a binary supported lipid bilayer (SLB) comprising dioleoylphosphatidylcholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC) were localized on graphene oxide (GO) deposited on a SiO₂/Si substrate. We investigated the distribution of the gel-phase domains and the liquid crystalline (L_α [...] Read more.

The gel-phase domains in a binary supported lipid bilayer (SLB) comprising dioleoylphosphatidylcholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC) were localized on graphene oxide (GO) deposited on a SiO₂/Si substrate. We investigated the distribution of the gel-phase domains and the liquid crystalline (L_α) phase regions in DOPC+DPPC-SLB on thermally oxidized SiO₂/Si substrates with GO flakes to understand the mechanism of the domain localization on GO. Fluorescence microscopy and atomic force microscopy revealed that the gel-phase domains preferably distributed on GO flakes, whereas the fraction of the L_α-phase increased on the bare SiO₂ surface which was not covered with the GO flakes. The gel-phase domain was condensed on GO more effectively at the lower cooling rate. We propose that nucleation of the gel-phase domain preferentially occurred on GO, whose surface has amphiphilic property, during the gel-phase domain formation. The domains of the liquid ordered (L_o) phase were also condensed on GO in a ternary bilayer containing cholesterol that was phase-separated to the L_o phase and the liquid disordered phase. Rigid domains segregates on GO during their formation process, leaving fluid components to the surrounding region of GO. Full article

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13 pages, 6108 KiB

Open AccessArticle

The Encapsulation of Natural Organic Dyes on TiO₂ for Photochromism Control

by Hye Ju Lee, Jong Won Shim, Jung Jin Lee and Won Jun Lee

Int. J. Mol. Sci. 2023, 24(9), 7860; https://doi.org/10.3390/ijms24097860 - 26 Apr 2023

Cited by 6 | Viewed by 2613

Abstract

Titanium dioxide (TiO₂) plays a pivotal role in photocatalytic reactions and holds great promise for the cosmetic and paint industries due to its white color and high refractive index. However, the original color of TiO₂ changes gradually to blue or [...] Read more.

Titanium dioxide (TiO₂) plays a pivotal role in photocatalytic reactions and holds great promise for the cosmetic and paint industries due to its white color and high refractive index. However, the original color of TiO₂ changes gradually to blue or yellow with UV irradiation, which affects its color realization. We encapsulated TiO₂ with several natural organic dye compounds, including purpurin, curcumin, and safflower, to control its photochromism and realize a range of different colors. The chemical reaction between TiO₂ and dyes based on their functional group was investigated, and the light absorption was tested via FTIR and UV–Vis spectroscopy. The changes in morphology and size distribution additionally supported their successful encapsulation. The discoloration after UV irradiation was evaluated by measuring the color difference (ΔE) of control TiO₂ and dye encapsulated TiO₂. The unique structure utilized natural dyes to preserve photochromism based on the physical barrier and automatically controlled the electronic transition of core TiO₂. In particular, the color difference values of purpurin and curcumin were 4.05 and 3.76, which is lower than the 5.36 of the control TiO₂. Dye encapsulated TiO₂ was manipulated into lipstick to verify its color realization and retention. Full article

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Graphical abstract

11 pages, 3638 KiB

Open AccessArticle

Molecule Clustering Dynamics in the Molecular Doping Process of Si(111) with Diethyl-propyl-phosphonate

by Mattia Pizzone, Maria Grazia Grimaldi, Antonino La Magna, Silvia Scalese, Jost Adam and Rosaria A. Puglisi

Int. J. Mol. Sci. 2023, 24(8), 6877; https://doi.org/10.3390/ijms24086877 - 7 Apr 2023

Viewed by 2034

Abstract

The molecular doping (MD) process is based on the deposition of dopant-containing molecules over the surface of a semiconductor substrate, followed by the thermal diffusion step. Previous studies suggest that, during the deposition, the molecules nucleate clusters, and at prolonged deposition times, they [...] Read more.

The molecular doping (MD) process is based on the deposition of dopant-containing molecules over the surface of a semiconductor substrate, followed by the thermal diffusion step. Previous studies suggest that, during the deposition, the molecules nucleate clusters, and at prolonged deposition times, they grow into self-assembled layers on the sample to be doped. Little is known about the influence of nucleation kinetics on the final properties of these layers and how they change when we modify the solution properties. In this work, we examine the nucleation rate and the molecular surface coverage kinetics of diethyl-propyl phosphonate on silicon at different solution concentrations and how these conditions influence the final electrical properties of the doped samples. We present a high-resolution morphological characterization of the as-deposited molecules together with the electrical results of the final doped samples. The experimental results show a non-obvious behavior, explained through understanding of the competition between the molecules’ physisorption and chemisorption mechanisms. As a consequence, due to the deeper knowledge of the deposition phase, a finer tuning of the conductive properties of MD-doped samples is achieved. Full article

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15 pages, 2959 KiB

Open AccessArticle

Bioglues Based on an Elastin-Like Recombinamer: Effect of Tannic Acid as an Additive on Tissue Adhesion and Cytocompatibility

by Alp Sarisoy, Sergio Acosta, José Carlos Rodríguez-Cabello, Phillip Czichowski, Alexander Kopp, Stefan Jockenhoevel and Alicia Fernández-Colino

Int. J. Mol. Sci. 2023, 24(7), 6776; https://doi.org/10.3390/ijms24076776 - 5 Apr 2023

Cited by 5 | Viewed by 3075

Abstract

More than 260 million surgical procedures are performed worldwide each year. Although sutures and staples are widely used to reconnect tissues, they can cause further damage and increase the risk of infection. Bioadhesives have been proposed as an alternative to reconnect tissues. However, [...] Read more.

More than 260 million surgical procedures are performed worldwide each year. Although sutures and staples are widely used to reconnect tissues, they can cause further damage and increase the risk of infection. Bioadhesives have been proposed as an alternative to reconnect tissues. However, clinical adhesives that combine strong adhesion with cytocompatibility have yet to be developed. In this study, we explored the production of adhesives based on protein-engineered polymers bioinspired by the sequence of elastin (i.e., elastin-like recombinamers, ELRs). We hypothesized that the combination of polyphenols (i.e., tannic acid, TA) and ELRs would produce an adhesive coacervate (ELR+TA), as reported for other protein polymers such as silk fibroin (SF). Notably, the adhesion of ELR alone surpassed that of ELR+TA. Indeed, ELR alone achieved adhesive strengths of 88.8 ± 33.2 kPa and 17.0 ± 2.0 kPa on porcine bone and skin tissues, respectively. This surprising result led us to explore a multicomponent bioadhesive to encompass the complementary roles of elastin (mimicked here by ELR) and silk fibroin (SF), and subsequently mirror more closely the multicomponent nature of the extracellular matrix. Tensile testing showed that ELR+SF achieved an adhesive strength of 123.3 ± 60.2 kPa on porcine bone and excellent cytocompatibility. To express this in a more visual and intuitive way, a small surface of only 2.5 cm² was able to lift at least 2 kg of weight. This opens the door for further studies focusing on the ability of protein-engineered polymers to adhere to biological tissues without further chemical modification for applications in tissue engineering. Full article

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17 pages, 3753 KiB

Open AccessArticle

High-Order Harmonics Generation in MoS₂ Transition Metal Dichalcogenides: Effect of Nickel and Carbon Nanotube Dopants

by Mottamchetty Venkatesh, Vyacheslav V. Kim, Ganjaboy S. Boltaev, Srinivasa Rao Konda, Peter Svedlindh, Wei Li and Rashid A. Ganeev

Int. J. Mol. Sci. 2023, 24(7), 6540; https://doi.org/10.3390/ijms24076540 - 31 Mar 2023

Cited by 5 | Viewed by 2678

Abstract

The transition metal dichalcogenides have instigated a lot of interest as harmonic generators due to their exceptional nonlinear optical properties. Here, the molybdenum disulfide (MoS₂) molecular structures with dopants being in a plasma state are used to demonstrate the generation of [...] Read more.

The transition metal dichalcogenides have instigated a lot of interest as harmonic generators due to their exceptional nonlinear optical properties. Here, the molybdenum disulfide (MoS₂) molecular structures with dopants being in a plasma state are used to demonstrate the generation of intense high-order harmonics. The MoS₂ nanoflakes and nickel-doped MoS₂ nanoflakes produced stronger harmonics with higher cut-offs compared with Mo bulk and MoS₂ bulk. Conversely, the MoS₂ with nickel nanoparticles and carbon nanotubes (MoS₂-NiCNT) produced weaker coherent XUV emissions than other materials, which is attributed to the influence of phase mismatch. The influence of heating and driving pulse intensities on the harmonic yield and cut-off energies are investigated in MoS₂ molecular structures. The enhanced coherent extreme ultraviolet emission at ~32 nm (38 eV) due to the 4p-4d resonant transitions is obtained from all aforementioned molecular structures, except for MoS₂-NiCNT. Full article

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17 pages, 7747 KiB

Open AccessArticle

Microstructural and Mechanical Characterization of Al Nanocomposites Using GCNs as a Reinforcement Fabricated by Induction Sintering

by Verónica Gallegos Orozco, Audel Santos Beltrán, Miriam Santos Beltrán, Hansel Medrano Prieto, Carmen Gallegos Orozco, Ivanovich Estrada Guel, Roberto Martínez Sánchez and José Manuel Mendoza Duarte

Int. J. Mol. Sci. 2023, 24(6), 5558; https://doi.org/10.3390/ijms24065558 - 14 Mar 2023

Viewed by 1508

Abstract

High-energy ball milling is a process suitable for producing composite powders whose achieved microstructure can be controlled by the processing parameters. Through this technique, it is possible to obtain a homogeneous distribution of reinforced material into a ductile metal matrix. In this work, [...] Read more.

High-energy ball milling is a process suitable for producing composite powders whose achieved microstructure can be controlled by the processing parameters. Through this technique, it is possible to obtain a homogeneous distribution of reinforced material into a ductile metal matrix. In this work, some Al/CGNs nanocomposites were fabricated through a high-energy ball mill to disperse nanostructured graphite reinforcements produced in situ in the Al matrix. To retain the dispersed CGNs in the Al matrix, avoiding the precipitation of the Al₄C₃ phase during sintering, the high-frequency induction sintering (HFIS) method was used, which allows rapid heating rates. For comparative purposes, samples in the green and sintered state processed in a conventional electric furnace (CFS) were used. Microhardness testing was used to evaluate the effectiveness of the reinforcement in samples under different processing conditions. Structural analyses were carried out through an X-ray diffractometer coupled with a convolutional multiple whole profile (CMWP) fitting program to determine the crystallite size and dislocation density; both strengthening contributions were calculated using the Langford–Cohen and Taylor equations. According to the results, the CGNs dispersed in the Al matrix played an important role in the reinforcement of the Al matrix, promoting the increase in the dislocation density during the milling process. The strengthening contribution of the dislocation density was ~50% of the total hardening value, while the contribution by dispersion of CGNs was ~22% in samples with 3 wt. % C and sintered by the HFIS method. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to analyze the morphology, size, and distribution of phases present in the Al matrix. From the analyses carried out in AFM (topography and phase images), the CGNs are located mainly around crystallites and present height profiles of 1.6 to 2 nm. Full article

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21 pages, 5149 KiB

Open AccessArticle

Application of Pyrolysis for the Evaluation of Organic Compounds in Medical Plastic Waste Generated in the City of Cartagena-Colombia Applying TG-GC/MS

by Joaquín Hernandez-Fernandez, Henry Lambis and Ricardo Vivas Reyes

Int. J. Mol. Sci. 2023, 24(6), 5397; https://doi.org/10.3390/ijms24065397 - 11 Mar 2023

Cited by 4 | Viewed by 2854

Abstract

In this study, the thermal degradation and pyrolysis of hospital plastic waste consisting of polyethylene (PE), polystyrene (PS), and polypropylene (PP) were investigated using TG-GC/MS. The identified molecules with the functional groups of alkanes, alkenes, alkynes, alcohols, aromatics, phenols, CO and CO₂ [...] Read more.

In this study, the thermal degradation and pyrolysis of hospital plastic waste consisting of polyethylene (PE), polystyrene (PS), and polypropylene (PP) were investigated using TG-GC/MS. The identified molecules with the functional groups of alkanes, alkenes, alkynes, alcohols, aromatics, phenols, CO and CO₂ were found in the gas stream from pyrolysis and oxidation, and are chemical structures with derivatives of aromatic rings. They are mainly related to the degradation of PS hospital waste, and the alkanes and alkenes groups originate mainly from PP and PE-based medical waste. The pyrolysis of this hospital waste did not show the presence of derivatives of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans, which is an advantage over classical incineration methodologies. CO, CO₂, phenol, acetic acid and benzoic acid concentrations were higher in the gases from the oxidative degradation than in those generated in the pyrolysis with helium. In this article, we propose different pathways of reaction mechanisms that allow us to explain the presence of molecules with other functional groups, such as alkanes, alkenes, carboxylic acids, alcohols, aromatics and permanent gases. Full article

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16 pages, 1817 KiB

Open AccessCommunication

Aptamers as Novel Binding Molecules on an Antimicrobial Peptide-Armored Composite Hydrogel Wound Dressing for Specific Removal and Efficient Eradication of Pseudomonas aeruginosa

by Markus Kraemer, Magali Bellion, Ann-Kathrin Kissmann, Tilmann Herberger, Christopher V. Synatschke, Anil Bozdogan, Jakob Andersson, Armando Rodriguez, Ludger Ständker, Sebastien Wiese, Steffen Stenger, Barbara Spellerberg, Kay-Eberhard Gottschalk, Ahmet Cetinkaya, Joanna Pietrasik, Tanja Weil and Frank Rosenau

Int. J. Mol. Sci. 2023, 24(5), 4800; https://doi.org/10.3390/ijms24054800 - 2 Mar 2023

Cited by 6 | Viewed by 4868

Abstract

Here we present for the first time a potential wound dressing material implementing aptamers as binding entities to remove pathogenic cells from newly contaminated surfaces of wound matrix-mimicking collagen gels. The model pathogen in this study was the Gram-negative opportunistic bacterium Pseudomonas aeruginosa [...] Read more.

Here we present for the first time a potential wound dressing material implementing aptamers as binding entities to remove pathogenic cells from newly contaminated surfaces of wound matrix-mimicking collagen gels. The model pathogen in this study was the Gram-negative opportunistic bacterium Pseudomonas aeruginosa, which represents a considerable health threat in hospital environments as a cause of severe infections of burn or post-surgery wounds. A two-layered hydrogel composite material was constructed based on an established eight-membered focused anti-P. aeruginosa polyclonal aptamer library, which was chemically crosslinked to the material surface to form a trapping zone for efficient binding of the pathogen. A drug-loaded zone of the composite released the C14R antimicrobial peptide to deliver it directly to the bound pathogenic cells. We demonstrate that this material combining aptamer-mediated affinity and peptide-dependent pathogen eradication can quantitatively remove bacterial cells from the “wound” surface, and we show that the surface-trapped bacteria are completely killed. The drug delivery function of the composite thus represents an extra safeguarding property and thus probably one of the most important additional advances of a next-generation or smart wound dressing ensuring the complete removal and/or eradication of the pathogen of a freshly infected wound. Full article

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19 pages, 14177 KiB

Open AccessArticle

Intracellular Nitric Oxide and cAMP Are Involved in Cellulolytic Enzyme Production in Neurospora crassa

by Nan-Nan Yu, Wirinthip Ketya and Gyungsoon Park

Int. J. Mol. Sci. 2023, 24(5), 4503; https://doi.org/10.3390/ijms24054503 - 24 Feb 2023

Cited by 4 | Viewed by 2152

Abstract

Although molecular regulation of cellulolytic enzyme production in filamentous fungi has been actively explored, the underlying signaling processes in fungal cells are still not clearly understood. In this study, the molecular signaling mechanism regulating cellulase production in Neurospora crassa was investigated. We found [...] Read more.

Although molecular regulation of cellulolytic enzyme production in filamentous fungi has been actively explored, the underlying signaling processes in fungal cells are still not clearly understood. In this study, the molecular signaling mechanism regulating cellulase production in Neurospora crassa was investigated. We found that the transcription and extracellular cellulolytic activity of four cellulolytic enzymes (cbh1, gh6-2, gh5-1, and gh3-4) increased in Avicel (microcrystalline cellulose) medium. Intracellular nitric oxide (NO) and reactive oxygen species (ROS) detected by fluorescent dyes were observed in larger areas of fungal hyphae grown in Avicel medium compared to those grown in glucose medium. The transcription of the four cellulolytic enzyme genes in fungal hyphae grown in Avicel medium was significantly decreased and increased after NO was intracellularly removed and extracellularly added, respectively. Furthermore, we found that the cyclic AMP (cAMP) level in fungal cells was significantly decreased after intracellular NO removal, and the addition of cAMP could enhance cellulolytic enzyme activity. Taken together, our data suggest that the increase in intracellular NO in response to cellulose in media may have promoted the transcription of cellulolytic enzymes and participated in the elevation of intracellular cAMP, eventually leading to improved extracellular cellulolytic enzyme activity. Full article

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12 pages, 3713 KiB

Open AccessArticle

Significance of MnO₂ Type and Solution Parameters in Manganese Removal from Water Solution

by Magdalena M. Michel, Mostafa Azizi, Dorota Mirosław-Świątek, Lidia Reczek, Bogumił Cieniek and Eleonora Sočo

Int. J. Mol. Sci. 2023, 24(5), 4448; https://doi.org/10.3390/ijms24054448 - 23 Feb 2023

Cited by 3 | Viewed by 2774

Abstract

A very low concentration of manganese (Mn) in water is a critical issue for municipal and industrial water supply systems. Mn removal technology is based on the use of manganese oxides (MnO_x), especially manganese dioxide (MnO₂) polymorphs, under different [...] Read more.

A very low concentration of manganese (Mn) in water is a critical issue for municipal and industrial water supply systems. Mn removal technology is based on the use of manganese oxides (MnO_x), especially manganese dioxide (MnO₂) polymorphs, under different conditions of pH and ionic strength (water salinity). The statistical significance of the impact of polymorph type (akhtenskite ε-MnO₂, birnessite δ-MnO₂, cryptomelane α-MnO₂ and pyrolusite β-MnO₂), pH (2–9) and ionic strength (1–50 mmol/L) of solution on the adsorption level of Mn was investigated. The analysis of variance and the non-parametric Kruskal–Wallis H test were applied. Before and after Mn adsorption, the tested polymorphs were characterized using X-ray diffraction, scanning electron microscope techniques and gas porosimetry analysis. Here we demonstrated the significant differences in adsorption level between MnO₂ polymorphs’ type and pH; however, the statistical analysis proves that the type of MnO₂ has a four times stronger influence. There was no statistical significance for the ionic strength parameter. We showed that the high adsorption of Mn on the poorly crystalline polymorphs leads to the blockage of micropores in akhtenskite and, contrary, causes the development of the surface structure of birnessite. At the same time, no changes in the surfaces of cryptomelane and pyrolusite, the highly crystalline polymorphs, were found due to the very small loading by the adsorbate. Full article

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26 pages, 3485 KiB

Open AccessReview

The Integration of Biopolymer-Based Materials for Energy Storage Applications: A Review

by Shrey Dalwadi, Arnav Goel, Constantine Kapetanakis, David Salas-de la Cruz and Xiao Hu

Int. J. Mol. Sci. 2023, 24(4), 3975; https://doi.org/10.3390/ijms24043975 - 16 Feb 2023

Cited by 19 | Viewed by 5377

Abstract

Biopolymers are an emerging class of novel materials with diverse applications and properties such as superior sustainability and tunability. Here, applications of biopolymers are described in the context of energy storage devices, namely lithium-based batteries, zinc-based batteries, and capacitors. Current demand for energy [...] Read more.

Biopolymers are an emerging class of novel materials with diverse applications and properties such as superior sustainability and tunability. Here, applications of biopolymers are described in the context of energy storage devices, namely lithium-based batteries, zinc-based batteries, and capacitors. Current demand for energy storage technologies calls for improved energy density, preserved performance overtime, and more sustainable end-of-life behavior. Lithium-based and zinc-based batteries often face anode corrosion from processes such as dendrite formation. Capacitors typically struggle with achieving functional energy density caused by an inability to efficiently charge and discharge. Both classes of energy storage need to be packaged with sustainable materials due to their potential leakages of toxic metals. In this review paper, recent progress in energy applications is described for biocompatible polymers such as silk, keratin, collagen, chitosan, cellulose, and agarose. Fabrication techniques are described for various components of the battery/capacitors including the electrode, electrolyte, and separators with biopolymers. Of these methods, incorporating the porosity found within various biopolymers is commonly used to maximize ion transport in the electrolyte and prevent dendrite formations in lithium-based, zinc-based batteries, and capacitors. Overall, integrating biopolymers in energy storage solutions poses a promising alternative that can theoretically match traditional energy sources while eliminating harmful consequences to the environment. Full article

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22 pages, 989 KiB

Open AccessArticle

Enzyme Conditioning of Chicken Collagen and Taguchi Design of Experiments Enhancing the Yield and Quality of Prepared Gelatins

by Pavel Mokrejš, Robert Gál and Jana Pavlačková

Int. J. Mol. Sci. 2023, 24(4), 3654; https://doi.org/10.3390/ijms24043654 - 11 Feb 2023

Cited by 1 | Viewed by 2311

Abstract

During the production of mechanically deboned chicken meat (MDCM), a by-product is created that has no adequate use and is mostly disposed of in rendering plants. Due to the high content of collagen, it is a suitable raw material for the production of [...] Read more.

During the production of mechanically deboned chicken meat (MDCM), a by-product is created that has no adequate use and is mostly disposed of in rendering plants. Due to the high content of collagen, it is a suitable raw material for the production of gelatin and hydrolysates. The purpose of the paper was to process the MDCM by-product into gelatin by 3-step extraction. An innovative method was used to prepare the starting raw material for gelatin extraction, demineralization in HCl, and conditioning with a proteolytic enzyme. A Taguchi design with two process factors (extraction temperature and extraction time) was used at three levels (42, 46, and 50 °C; 20, 40, and 60 min) to optimize the processing of the MDCM by-product into gelatins. The gel-forming and surface properties of the prepared gelatins were analyzed in detail. Depending on the processing conditions, gelatins are prepared with a gel strength of up to 390 Bloom, a viscosity of 0.9–6.8 mPa·s, a melting point of 29.9–38.4 °C, a gelling point of 14.9–17.6 °C, excellent water- and fat-holding capacity, and good foaming and emulsifying capacity and stability. The advantage of MDCM by-product processing technology is a very high degree of conversion (up to 77%) of the starting collagen raw material to gelatins and the preparation of 3 qualitatively different gelatin fractions suitable for a wide range of food, pharmaceutical, and cosmetic applications. Gelatins prepared from MDCM by-product can expand the offer of gelatins from other than beef and pork tissues. Full article

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15 pages, 3478 KiB

Open AccessArticle

Insight into the Molecule Impact of Critical-Sized UHMWPE-ALN Wear Particles on Cells by the Alginate-Encapsulated Cell Reactor

by Yumei Liu, Feng Shi and Shuxin Qu

Int. J. Mol. Sci. 2023, 24(4), 3510; https://doi.org/10.3390/ijms24043510 - 9 Feb 2023

Cited by 3 | Viewed by 2238

Abstract

Wear particles of ultra-high molecular weight polyethylene (UHMWPE) are inevitable during service as joint prosthesis, and particles ≤ 10 μm with critical size could cause serious osteolysis and aseptic loosening of joint prosthesis. The aim of this study is to adopt the alginate-encapsulated [...] Read more.

Wear particles of ultra-high molecular weight polyethylene (UHMWPE) are inevitable during service as joint prosthesis, and particles ≤ 10 μm with critical size could cause serious osteolysis and aseptic loosening of joint prosthesis. The aim of this study is to adopt the alginate-encapsulated cell reactor to investigate the molecular impact of critical-sized wear particles of UHMWPE loaded with alendronate sodium (UHMWPE-ALN) on cells. Results showed that compared with UHMWPE wear particles, UHMWPE-ALN wear particles inhibited the proliferation of macrophages significantly after being co-cultured for 1, 4, 7, and 14 d. Furthermore, the released ALN promoted early apoptosis, suppressed the secretion of TNF-α and IL-6 of macrophages, and down-regulated relative gene expressions of TNF-α, IL-6, and IL-1β and RANK. In addition, compared with UHMWPE wear particles, UHMWPE-ALN wear particles promoted the ALP activity of osteoblasts, down-regulated the gene expression of RANKL, and up-regulated gene expression of osteoprotegerin. There were mainly two approaches of the effects of critical-sized UHMWPE-ALN wear particles on cells, one of which was cytology and the other was cytokine signal pathway. The former mainly affected the proliferation and activity of macrophages and osteoblasts. The latter would inhibit osteoclasts via cytokine and RANKL/RANK signal pathway. Thus, UHMWPE-ALN had the potential application in clinics to treat osteolysis induced by wear particles. Full article

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20 pages, 3198 KiB

Open AccessArticle

Unusual Square Pyramidal Chalcogenide Mo₅ Cluster with Bridging Pyrazolate-Ligands

by Iulia V. Savina, Anton A. Ivanov, Darya V. Evtushok, Yakov M. Gayfulin, Andrey Y. Komarovskikh, Mikhail M. Syrokvashin, Mariia N. Ivanova, Igor P. Asanov, Ilia V. Eltsov, Natalia V. Kuratieva, Yuri V. Mironov and Michael A. Shestopalov

Int. J. Mol. Sci. 2023, 24(4), 3440; https://doi.org/10.3390/ijms24043440 - 8 Feb 2023

Cited by 3 | Viewed by 2393

Abstract

The family of chalcogenide molybdenum clusters is well presented in the literature by a series of compounds of nuclearity ranging from binuclear to multinuclear articulating octahedral fragments. Clusters actively studied in the last decades were shown to be promising as components of superconducting, [...] Read more.

The family of chalcogenide molybdenum clusters is well presented in the literature by a series of compounds of nuclearity ranging from binuclear to multinuclear articulating octahedral fragments. Clusters actively studied in the last decades were shown to be promising as components of superconducting, magnetic, and catalytic systems. Here, we report the synthesis and detailed characterization of new and unusual representatives of chalcogenide clusters: square pyramidal complexes [{Mo₅(μ₃-Se)ⁱ₄(μ₄-Se)ⁱ(μ-pz)ⁱ₄}(pzH)^t₅]^1+/2+ (pzH = pyrazole, i = inner, t = terminal). Individually obtained oxidized (2+) and reduced (1+) forms have very close geometry (proven by single-crystal X-ray diffraction analysis) and are able to reversibly transform into each other, which was confirmed by cyclic voltammetry. Comprehensive characterization of the complexes, both in solid and in solution, confirms the different charge state of molybdenum in clusters (XPS), magnetic properties (EPR), and so on. DFT calculations complement the diverse study of new complexes, expanding the chemistry of molybdenum chalcogenide clusters. Full article

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22 pages, 3812 KiB

Open AccessArticle

Response Surface Methodology to Efficiently Optimize Intracellular Delivery by Photoporation

by Ilia Goemaere, Deep Punj, Aranit Harizaj, Jessica Woolston, Sofie Thys, Karen Sterck, Stefaan C. De Smedt, Winnok H. De Vos and Kevin Braeckmans

Int. J. Mol. Sci. 2023, 24(4), 3147; https://doi.org/10.3390/ijms24043147 - 5 Feb 2023

Cited by 9 | Viewed by 3457

Abstract

Photoporation is an up-and-coming technology for the gentle and efficient transfection of cells. Inherent to the application of photoporation is the optimization of several process parameters, such as laser fluence and sensitizing particle concentration, which is typically done one factor at a time [...] Read more.

Photoporation is an up-and-coming technology for the gentle and efficient transfection of cells. Inherent to the application of photoporation is the optimization of several process parameters, such as laser fluence and sensitizing particle concentration, which is typically done one factor at a time (OFAT). However, this approach is tedious and runs the risk of missing a global optimum. Therefore, in this study, we explored whether response surface methodology (RSM) would allow for more efficient optimization of the photoporation procedure. As a case study, FITC-dextran molecules of 500 kDa were delivered to RAW264.7 mouse macrophage-like cells, making use of polydopamine nanoparticles (PDNPs) as photoporation sensitizers. Parameters that were varied to obtain an optimal delivery yield were PDNP size, PDNP concentration and laser fluence. Two established RSM designs were compared: the central composite design and the Box-Behnken design. Model fitting was followed by statistical assessment, validation, and response surface analysis. Both designs successfully identified a delivery yield optimum five- to eight-fold more efficiently than when using OFAT methodology while revealing a strong dependence on PDNP size within the design space. In conclusion, RSM proves to be a valuable approach to efficiently optimize photoporation conditions for a particular cell type. Full article

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16 pages, 2625 KiB

Open AccessArticle

Mechanical Properties of Twisted Carbon Nanotube Bundles with Carbon Linkers from Molecular Dynamics Simulations

by Andrea Pedrielli, Maurizio Dapor, Konstantinos Gkagkas, Simone Taioli and Nicola Maria Pugno

Int. J. Mol. Sci. 2023, 24(3), 2473; https://doi.org/10.3390/ijms24032473 - 27 Jan 2023

Cited by 7 | Viewed by 2490

Abstract

The manufacturing of high-modulus, high-strength fibers is of paramount importance for real-world, high-end applications. In this respect, carbon nanotubes represent the ideal candidates for realizing such fibers. However, their remarkable mechanical performance is difficult to bring up to the macroscale, due to the [...] Read more.

The manufacturing of high-modulus, high-strength fibers is of paramount importance for real-world, high-end applications. In this respect, carbon nanotubes represent the ideal candidates for realizing such fibers. However, their remarkable mechanical performance is difficult to bring up to the macroscale, due to the low load transfer within the fiber. A strategy to increase such load transfer is the introduction of chemical linkers connecting the units, which can be obtained, for example, using carbon ion-beam irradiation. In this work, we investigate, via molecular dynamics simulations, the mechanical properties of twisted nanotube bundles in which the linkers are composed of interstitial single carbon atoms. We find a significant interplay between the twist and the percentage of linkers. Finally, we evaluate the suitability of two different force fields for the description of these systems: the dihedral-angle-corrected registry-dependent potential, which we couple for non-bonded interaction with either the AIREBO potential or the screened potential ReboScr2. We show that both of these potentials show some shortcomings in the investigation of the mechanical properties of bundles with carbon linkers. Full article

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13 pages, 7282 KiB

Open AccessArticle

An In-Situ Fabrication Method of ZnO and Other Zn(II) Compounds Containing Polypropylene Composites

by Katarzyna Kupińska, Maciej Michalik, Justyna Krajenta, Magda Bielicka, Karolina Halina Markiewicz, Beata Kalska-Szostko and Agnieszka Zofia Wilczewska

Int. J. Mol. Sci. 2023, 24(3), 2357; https://doi.org/10.3390/ijms24032357 - 25 Jan 2023

Cited by 4 | Viewed by 2377

Abstract

This study investigated the methods of preparation of zinc oxide-polypropylene nanocomposites and their antibacterial properties. Seven solutions with ZnO nanoparticles or zinc ions were formulated as a PP additive. Two methods of ZnO NPs syntheses were carried out: (1) a modified hydrothermal method [...] Read more.

This study investigated the methods of preparation of zinc oxide-polypropylene nanocomposites and their antibacterial properties. Seven solutions with ZnO nanoparticles or zinc ions were formulated as a PP additive. Two methods of ZnO NPs syntheses were carried out: (1) a modified hydrothermal method where a water solution of zinc acetate dihydrate, PEI, and ammonia were mixed with a final pH 11; (2) a thermal decomposition of a water solution of zinc acetate in the presence of PEI and ammonia using a two-screw extruder. During the experiments, the influence of various amounts of particle stabilizer, heating of the solutions, and the temperatures of the syntheses were examined. As a result, the simultaneous crystallization of ZnO in the extrusion process confirmed this method’s attractiveness from the application point of view. Fabricated PP-ZnO composite shows antibacterial properties against Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae. Full article

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23 pages, 9773 KiB

Open AccessArticle

High Temperature CO₂ Capture Performance and Kinetic Analysis of Novel Potassium Stannate

by Ross Baird, Ribooga Chang, Ocean Cheung and Aimaro Sanna

Int. J. Mol. Sci. 2023, 24(3), 2321; https://doi.org/10.3390/ijms24032321 - 24 Jan 2023

Cited by 2 | Viewed by 2299

Abstract

For the first time, the use of stannate-based sorbents was investigated as high temperature CO₂ sorption to evaluate their potential to contribute towards reducing carbon emissions. The sorption capacity and kinetics of commercial tin oxide, sodium, potassium and calcium stannates and lab [...] Read more.

For the first time, the use of stannate-based sorbents was investigated as high temperature CO₂ sorption to evaluate their potential to contribute towards reducing carbon emissions. The sorption capacity and kinetics of commercial tin oxide, sodium, potassium and calcium stannates and lab synthesised potassium stannates were tested using thermogravimetric analysis. Commercial K₂SnO₃ was found to possess the largest CO₂ uptake capacity (2.77 mmol CO₂/g or 12.2 wt%) at 700 °C, which is among the highest for potassium sorbents, but the CO₂ desorption was not successful. On the contrary, the in-house synthesised K-stannate (K-B) using facile solid-state synthesis outperformed the other sorbents, resulting in a CO₂ uptake of 7.3 wt% after 5 min, an adsorption rate (0.016 mg/s) one order of magnitude higher than the other stannates, and stability after 40 cycles. The XRD and XPS analyses showed that K-B contains a mixture of K₂SnO₃ (76%) and K₄SnO₄ (21%), while the Scherrer crystal sizes confirmed good resistance to sintering for the potassium stannates. Among the apparent kinetic model tested, the pseudo-second order model was the most suitable to predict the CO₂ sorption process of K-B, indicating that chemical adsorption is dominant, while film-diffusion resistance and intra-particle diffusion resistance governed the sorption process in K-B. In summary, this work shows that solid-state synthesised potassium stannate could be an effective sorbent for high temperature separation, and additional work is required to further elucidate its potential. Full article

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13 pages, 4969 KiB

Open AccessArticle

Insight into the Varying Reactivity of Different Catalysts for CO₂ Cycloaddition into Styrene Oxide: An Experimental and DFT Study

by Angelo Pio Sebaaly, Hugo Dias, Lorraine Christ, Lynda Merzoud, Henry Chermette, Guillaume Hoffmann and Christophe Morell

Int. J. Mol. Sci. 2023, 24(3), 2123; https://doi.org/10.3390/ijms24032123 - 20 Jan 2023

Cited by 2 | Viewed by 2307

Abstract

The cycloaddition of CO₂ into epoxides to form cyclic carbonates is a highly sought-after reaction for its potential to both reduce and use CO₂, which is a greenhouse gas. In this paper, we present experimental and theoretical studies and a [...] Read more.

The cycloaddition of CO₂ into epoxides to form cyclic carbonates is a highly sought-after reaction for its potential to both reduce and use CO₂, which is a greenhouse gas. In this paper, we present experimental and theoretical studies and a mechanistic approach for three catalytic systems. First, as Lewis base catalysts, imidazole and its derivatives, then as a Lewis acid catalyst, ZnI₂ alone, and after that, the combined system of ZnI₂ and imidazole. In the former, we aimed to discover the reasons for the varied reactivities of five Lewis base catalysts. Furthermore, we succeeded in reproducing the experimental results and trends using DFT. To add, we emphasized the importance of non-covalent interactions and their role in reactivity. In our case, the presence of a hydrogen bond was a key factor in decreasing the reactivity of some catalysts, thus leading to lower conversion rates. Finally, mechanistically understanding this 100% atom economy reaction can aid experimental chemists in designing better and more efficient catalytic systems. Full article

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17 pages, 3974 KiB

Open AccessArticle

New Preparative Approach to Purer Technetium-99 Samples—Tetramethylammonium Pertechnetate: Deep Understanding and Application of Crystal Structure, Solubility, and Its Conversion to Technetium Zero Valent Matrix

by Mikhail A. Volkov, Anton P. Novikov, Mikhail S. Grigoriev, Vitaly V. Kuznetsov, Anastasiia V. Sitanskaia, Elena V. Belova, Andrey V. Afanasiev, Iurii M. Nevolin and Konstantin E. German

Int. J. Mol. Sci. 2023, 24(3), 2015; https://doi.org/10.3390/ijms24032015 - 19 Jan 2023

Cited by 2 | Viewed by 2626

Abstract

⁹⁹Tc is one of the predominant fission products of ²³⁵U and an important component of nuclear industry wastes. The long half-life and specific activity of ⁹⁹Tc (212,000 y, 0.63 GBq g⁻¹) makes Tc a hazardous material. Two principal [...] Read more.

⁹⁹Tc is one of the predominant fission products of ²³⁵U and an important component of nuclear industry wastes. The long half-life and specific activity of ⁹⁹Tc (212,000 y, 0.63 GBq g⁻¹) makes Tc a hazardous material. Two principal ways were proposed for its disposal, namely, long-term storage and transmutation. Conversion to metal-like technetium matrices is highly desirable for both cases and for the second one the reasonably high Tc purity was important too. Tetramethylammonium pertechnetate (TMAP) was proposed here as a prospective precursor for matrix manufacture. It provided with very high decontamination factors from actinides (that is imperative for transmutation) by means of recrystallisation and it was based on the precise data on TMAP solubility and thermodynamics accomplished in the temperature range of 3–68 °C. The structure of solid pertechnetates were re-estimated with precise X-ray structure solution and compared to its Re and Cl analogues and tetrabutylammonium analogue as well. Differential thermal and evolved gas analysis in a flow of Ar–5% H₂ gas mixture showed that the major products of thermolysis were pure metallic technetium in solid matrix, trimethylammonium, carbon dioxide, and water in gas phase. High decontamination factors have been achieved when TMAP was used as an intermediate precursor for Tc. Full article

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29 pages, 6214 KiB

Open AccessReview

Targeting Agents in Biomaterial-Mediated Bone Regeneration

by Miguel Gisbert-Garzarán, María Natividad Gómez-Cerezo and María Vallet-Regí

Int. J. Mol. Sci. 2023, 24(3), 2007; https://doi.org/10.3390/ijms24032007 - 19 Jan 2023

Cited by 3 | Viewed by 3086

Abstract

Bone diseases are a global public concern that affect millions of people. Even though current treatments present high efficacy, they also show several side effects. In this sense, the development of biocompatible nanoparticles and macroscopic scaffolds has been shown to improve bone regeneration [...] Read more.

Bone diseases are a global public concern that affect millions of people. Even though current treatments present high efficacy, they also show several side effects. In this sense, the development of biocompatible nanoparticles and macroscopic scaffolds has been shown to improve bone regeneration while diminishing side effects. In this review, we present a new trend in these materials, reporting several examples of materials that specifically recognize several agents of the bone microenvironment. Briefly, we provide a subtle introduction to the bone microenvironment. Then, the different targeting agents are exposed. Afterward, several examples of nanoparticles and scaffolds modified with these agents are shown. Finally, we provide some future perspectives and conclusions. Overall, this topic presents high potential to create promising translational strategies for the treatment of bone-related diseases. We expect this review to provide a comprehensive description of the incipient state-of-the-art of bone-targeting agents in bone regeneration. Full article

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20 pages, 9566 KiB

Open AccessArticle

In Vivo Degradation Behavior of Magnesium Alloy for Bone Implants with Improving Biological Activity, Mechanical Properties, and Corrosion Resistance

by Shun-Yi Jian, Chiu-Feng Lin, Tung-Lin Tsai, Pei-Hua Wang, Chung-Hwan Chen, Sung-Yen Lin and Chun-Chieh Tseng

Int. J. Mol. Sci. 2023, 24(2), 1602; https://doi.org/10.3390/ijms24021602 - 13 Jan 2023

Cited by 11 | Viewed by 3274

Abstract

This study aimed to establish a surface modification technology for ZK60 magnesium alloy implants that can degrade uniformly over time and promote bone healing. It proposes a special micro-arc oxidation (MAO) treatment on ZK60 alloy that enables the composite electrolytes to create a [...] Read more.

This study aimed to establish a surface modification technology for ZK60 magnesium alloy implants that can degrade uniformly over time and promote bone healing. It proposes a special micro-arc oxidation (MAO) treatment on ZK60 alloy that enables the composite electrolytes to create a coating with better corrosion resistance and solve the problems of uneven and excessive degradation. A magnesium alloy bone screw made in this way was able to promote the bone healing reaction after implantation in rabbits. Additionally, it was found that the MAO-treated samples could be sustained in simulated body-fluid solution, exhibiting excellent corrosion resistance and electrochemical stability. The Ca ions deposited in the MAO coating were not cytotoxic and were beneficial in enhancing bone healing after implantation. Full article

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11 pages, 3902 KiB

Open AccessArticle

Superfast Capture of Iodine from Air, Water, and Organic Solvent by Potential Dithiocarbamate-Based Organic Polymer

by Liya Thurakkal, Subba Rao Cheekatla and Mintu Porel

Int. J. Mol. Sci. 2023, 24(2), 1466; https://doi.org/10.3390/ijms24021466 - 11 Jan 2023

Cited by 7 | Viewed by 3255

Abstract

Organic polymers are widely explored due to their high stability, scalability, and more facile modification properties. We developed cost-effective dithiocarbamate-based organic polymers synthesized using diamides, carbon disulfide, and diamines to apply for environmental remediation. The sequestration of radioiodine is a serious concern to [...] Read more.

Organic polymers are widely explored due to their high stability, scalability, and more facile modification properties. We developed cost-effective dithiocarbamate-based organic polymers synthesized using diamides, carbon disulfide, and diamines to apply for environmental remediation. The sequestration of radioiodine is a serious concern to tackle when dealing with nuclear power for energy requirements. However, many of the current sorbents have the problem of slower adsorption for removing iodine. In this report, we discuss the utilization of an electron-rich dithiocarbamate-based organic polymer for the removal of iodine in a very short time and with high uptake. Our material showed 2.8 g/g uptake of vapor iodine in 1 h, 915.19 mg/g uptake of iodine from cyclohexane within 5 s, 93% removal of saturated iodine from water in 1 min, and 1250 mg/g uptake of triiodide ions from water within 30 s. To the best of our knowledge, the iodine capture was faster than previously observed for any existing material. The material was fully recyclable when applied for up to four cycles. Hence, this dithiocarbamate-based polymer can be a promising system for the fast removal of various forms of iodine and, thus, enhance environmental security. Full article

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2022

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21 pages, 5397 KiB

Open AccessArticle

Synthesis, Photochemistry, Computational Study and Potential Application of New Styryl-Thiophene and Naphtho-Thiophene Benzylamines

by Milena Mlakić, Ilijana Odak, Ivan Faraho, Martina Bosnar, Mihailo Banjanac, Zlata Lasić, Željko Marinić, Danijela Barić and Irena Škorić

Int. J. Mol. Sci. 2023, 24(1), 610; https://doi.org/10.3390/ijms24010610 - 29 Dec 2022

Cited by 2 | Viewed by 2158

Abstract

In this research, the synthesis, photochemistry, and computational study of new cis- and trans-isomers of amino-thienostilbenes is performed to test the efficiency of their production and acid resistance, and to investigate their electronic structure, photoreactivity, photophysical characteristics, and potential biological activity. [...] Read more.

In this research, the synthesis, photochemistry, and computational study of new cis- and trans-isomers of amino-thienostilbenes is performed to test the efficiency of their production and acid resistance, and to investigate their electronic structure, photoreactivity, photophysical characteristics, and potential biological activity. The electronic structure and conformations of synthesized thienostilbene amines and their photocyclization products are examined computationally, along with molecular modeling of amines possessing two thiophene rings that showed inhibitory potential toward cholinesterases. New amino-styryl thiophenes, with favorable photophysical properties and proven acid resistance, represent model compounds for their water-soluble ammonium salts as potential styryl optical dyes. The comparison with organic dyes possessing a trans-aminostilbene subunit as the scaffold shows that the newly synthesized trans-aminostilbenes have very similar absorbance wavelengths. Furthermore, their functionalized cis-isomers and photocyclization products are good candidates for cholinesterase inhibitors because of the structural similarity of the molecular skeleton to some already proven bioactive derivatives. Full article

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25 pages, 7170 KiB

Open AccessArticle

PEO Coatings Modified with Halloysite Nanotubes: Composition, Properties, and Release Performance

by Igor Imshinetskiy, Victoria Kashepa, Konstantine Nadaraia, Dmitry Mashtalyar, Sergey Suchkov, Pavel Zadorozhny, Aleksander Ustinov, Sergey Sinebryukhov and Sergey Gnedenkov

Int. J. Mol. Sci. 2023, 24(1), 305; https://doi.org/10.3390/ijms24010305 - 24 Dec 2022

Cited by 20 | Viewed by 2119

Abstract

In this work, the properties of the coatings formed on the Mg-Mn-Ce alloy by plasma electrolytic oxidation (PEO) in electrolytes containing halloysite nanotubes (HNTs) were investigated. The incorporation of halloysite nanotubes into the PEO coatings improved their mechanical characteristics, increased thickness, and corrosion [...] Read more.

In this work, the properties of the coatings formed on the Mg-Mn-Ce alloy by plasma electrolytic oxidation (PEO) in electrolytes containing halloysite nanotubes (HNTs) were investigated. The incorporation of halloysite nanotubes into the PEO coatings improved their mechanical characteristics, increased thickness, and corrosion resistance. The studied layers reduced corrosion current density by more than two times in comparison with the base PEO layer without HNTs (from 1.1 × 10⁻⁷ A/cm² to 4.9 × 10⁻⁸ A/cm²). The presence of halloysite nanotubes and products of their dihydroxylation that were formed under the PEO conditions had a positive impact on the microhardness of the obtained layers (this parameter increased from 4.5 ± 0.4 GPa to 7.3 ± 0.5 GPa). In comparison with the base PEO layer, coatings containing halloysite nanotubes exhibited sustained release and higher adsorption capacity regarding caffeine. Full article

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28 pages, 7020 KiB

Open AccessArticle

Removal of Pb²⁺, CrT, and Hg²⁺ Ions from Aqueous Solutions Using Amino-Functionalized Magnetic Nanoparticles

by A. F. P. Allwin Mabes Raj, Maja Bauman, Marijana Lakić, Nena Dimitrušev, Aleksandra Lobnik and Aljoša Košak

Int. J. Mol. Sci. 2022, 23(24), 16186; https://doi.org/10.3390/ijms232416186 - 19 Dec 2022

Cited by 14 | Viewed by 2408

Abstract

In this paper, a circular economy approach with the adsorption and desorption of heavy metal (HM) ions—i.e., lead (Pb²⁺), chromium (CrT), and mercury (Hg²⁺)—from aqueous solutions was studied. Specific and selective binding of HM ions was performed on stabilized [...] Read more.

In this paper, a circular economy approach with the adsorption and desorption of heavy metal (HM) ions—i.e., lead (Pb²⁺), chromium (CrT), and mercury (Hg²⁺)—from aqueous solutions was studied. Specific and selective binding of HM ions was performed on stabilized and amino-functionalized iron oxide magnetic nanoparticles (γ-Fe₂O₃@NH₂ NPs) from an aqueous solution at pH 4 and 7. For this purpose, γ-Fe₂O₃@NH₂ NPs were characterized by thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), specific surface area (BET), transmission electron microscopy (TEM), EDXS, and zeta potential measurements (ζ). The effects of different adsorbent amounts (m_ads = 20/45/90 mg) and the type of anions (NO₃⁻, Cl⁻, SO₄²⁻) on adsorption efficiency were also tested. The desorption was performed with 0.1 M HNO₃. The results showed improvement of adsorption efficiency for CrT, Pb²⁺, and Hg²⁺ ions at pH 7 by 45 mg of g-Fe₂O₃@NH₂ NPs, and the sequence was as follows: CrT > Hg²⁺ > Pb²⁺, with adsorption capacities of 90.4 mg/g, 85.6 mg/g, and 83.6 mg/g, respectively. The desorption results showed the possibility for the reuse of γ-Fe₂O₃@NH₂ NPs with HNO₃, as the desorption efficiency was 100% for Hg²⁺ ions, 96.7% for CrT, and 91.3% for Pb²⁺. Full article

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19 pages, 5311 KiB

Open AccessArticle

New Gd³⁺ and Mn²⁺-Co-Doped Scheelite-Type Ceramics—Their Structural, Optical and Magnetic Properties

by Hubert Fuks, Paweł Kochmański and Elżbieta Tomaszewicz

Int. J. Mol. Sci. 2022, 23(24), 15740; https://doi.org/10.3390/ijms232415740 - 12 Dec 2022

Cited by 1 | Viewed by 1509

Abstract

New Gd³⁺- and Mn²⁺-co-doped calcium molybdato-tungstates with the chemical formula of Ca_1−3x−yMn_y▯_xGd_2x(MoO₄)_1−3x(WO₄)_3x (labeled later as CaMnGdMoWO), where ▯ [...] Read more.

New Gd³⁺- and Mn²⁺-co-doped calcium molybdato-tungstates with the chemical formula of Ca_1−3x−yMn_y▯_xGd_2x(MoO₄)_1−3x(WO₄)_3x (labeled later as CaMnGdMoWO), where ▯ denotes vacant sites in the crystal lattice, 0 < x ≤ 0.2500 and y = 0.0200 as well as 0 < y ≤ 0.0667 and x = 0.1667 were successfully synthesized by high-temperature solid-state reaction method and combustion route. Obtained ceramic materials crystallize in scheelite-type structure with space group I4₁/a. Morphological features and grain sizes of powders under study were investigated by SEM technique. Spectroscopic studies within the UV-vis spectral range were carried out to estimate the direct band gap (E_g) and Urbach energy (E_U) of obtained powders. EPR studies confirmed the existence of two types of magnetic objects, i.e., Mn²⁺ and Gd³⁺ ions, and significant antiferromagnetic (AFM) interactions among them. Full article

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17 pages, 2593 KiB

Open AccessArticle

A Predictive Pharmacokinetic Model for Immune Cell-Mediated Uptake and Retention of Nanoparticles in Tumors

by Ailton Sousa-Junior, Chun-Ting Yang, Preethi Korangath, Robert Ivkov and Andris Bakuzis

Int. J. Mol. Sci. 2022, 23(24), 15664; https://doi.org/10.3390/ijms232415664 - 10 Dec 2022

Cited by 6 | Viewed by 2073

Abstract

A promise of cancer nanomedicine is the “targeted” delivery of therapeutic agents to tumors by the rational design of nanostructured materials. During the past several decades, a realization that in vitro and in vivo preclinical data are unreliable predictors of successful clinical translation [...] Read more.

A promise of cancer nanomedicine is the “targeted” delivery of therapeutic agents to tumors by the rational design of nanostructured materials. During the past several decades, a realization that in vitro and in vivo preclinical data are unreliable predictors of successful clinical translation has motivated a reexamination of this approach. Mathematical models of drug pharmacokinetics (PK) and biodistribution (BD) are essential tools for small-molecule drugs development. A key assumption underlying these models is that drug-target binding kinetics dominate blood clearance, hence recognition by host innate immune cells is not explicitly included. Nanoparticles circulating in the blood are conspicuous to phagocytes, and inevitable interactions typically trigger active biological responses to sequester and remove them from circulation. Our recent findings suggest that, instead of referring to nanoparticles as designed for active or passive “tumor targeting”, we ought rather to refer to immune cells residing in the tumor microenvironment (TME) as active or passive actors in an essentially “cell-mediated tumor retention” process that competes with active removal by other phagocytes. Indeed, following intravenous injection, nanoparticles induce changes in the immune compartment of the TME because of nanoparticle uptake, irrespective of the nature of tumor targeting moieties. In this study, we propose a 6-compartment PK model as an initial mathematical framework for modeling this tumor-associated immune cell-mediated retention. Published in vivo PK and BD results obtained with bionized nanoferrite^® (BNF^®) nanoparticles were combined with results from in vitro internalization experiments with murine macrophages to guide simulations. As a preliminary approximation, we assumed that tumor-associated macrophages (TAMs) are solely responsible for active retention in the TME. We model the TAM approximation by relating in vitro macrophage uptake to an effective macrophage avidity term for the BNF^® nanoparticles under consideration. Full article

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13 pages, 2303 KiB

Open AccessArticle

Synthesis of Hybrid Epoxy Methacrylate Resin Based on Diglycidyl Ethers and Coatings Preparation via Cationic and Free-Radical Photopolymerization

by Paulina Bednarczyk, Izabela Irska, Konrad Gziut, Karolina Mozelewska and Paula Ossowicz-Rupniewska

Int. J. Mol. Sci. 2022, 23(24), 15592; https://doi.org/10.3390/ijms232415592 - 9 Dec 2022

Cited by 1 | Viewed by 2106

Abstract

A series of difunctional epoxy methacrylate resins (EAs) containing at least one epoxy and at least one methacrylate group were synthesized by means of an addition reaction between epoxy-terminated diglycidyl ethers and methacrylic acid. In order to investigate the impact of polymer architecture [...] Read more.

A series of difunctional epoxy methacrylate resins (EAs) containing at least one epoxy and at least one methacrylate group were synthesized by means of an addition reaction between epoxy-terminated diglycidyl ethers and methacrylic acid. In order to investigate the impact of polymer architecture on the course of addition reactions and further coating properties, several different types of diglycidyl ethers, i.e., linear, containing aliphatic or aromatic rings, with a short or polymeric backbone, were employed in the synthesis. The carboxyl–epoxide addition esterification reactions have been found to, in a relatively straightforward manner, control the extent of acrylation depending on the substrate feed ratio and reaction time. The structure of obtained pre-polymers was evaluated by FT-IR and NMR methods. At the same time, the extent of addition reactions was validated via quantitative analysis, including non-volatile matter content (NV), acid value (PAVs), and epoxy equivalent value (EE) analysis. The modification was carried out in a manner likely to create a compound with one epoxy and one carbon–carbon pendant group. Hence, due to the presence of both functionalities, it is possible to crosslink compositions based on synthesized EAs via two distinct mechanisms: (i) cationic polymerization or (ii) free-radical polymerization. Synthesized epoxy methacrylate pre-polymers were further employed for use in formulate photocurable coating compositions by the cationic or radical process. Furthermore, the photopolymerization behavior and properties of cured coatings were explored regarding some structural factors and parameters. The investigated polymeric materials cure in a short time to obtain coatings with good properties, which is why they can be successfully used to produce protective and decorative coatings for many industries. Full article

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12 pages, 4050 KiB

Open AccessArticle

Competing Routes in the Extraction of Lanthanide Nitrates by 1,10-Phenanthroline-2,9-diamides: An Impact of Structure of Complexes on the Extraction

by Yuri A. Ustynyuk, Nelly I. Zhokhova, Igor P. Gloriozov, Petr I. Matveev, Mariia V. Evsiunina, Pavel S. Lemport, Anton S. Pozdeev, Vladimir G. Petrov, Alexandr V. Yatsenko, Viktor A. Tafeenko and Valentine G. Nenajdenko

Int. J. Mol. Sci. 2022, 23(24), 15538; https://doi.org/10.3390/ijms232415538 - 8 Dec 2022

Cited by 13 | Viewed by 2047

Abstract

The fact of the fracture of the extraction curve of lanthanides by 1,10-phenanthroline-2,9-diamides is explained in terms of the structure of complexes, solvent extraction data and quantum chemical calculations. The solvent extraction proceeds in two competing directions: in the form of neutral complexes [...] Read more.

The fact of the fracture of the extraction curve of lanthanides by 1,10-phenanthroline-2,9-diamides is explained in terms of the structure of complexes, solvent extraction data and quantum chemical calculations. The solvent extraction proceeds in two competing directions: in the form of neutral complexes LLn(NO₃)₃ and in the form of tight ion pairs {[LLn(NO₃)₂ H₂O]⁺ (NO₃⁻). Full article

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14 pages, 3442 KiB

Open AccessArticle

Nanocomposites of Nitrogen-Doped Graphene Oxide and Manganese Oxide for Photodynamic Therapy and Magnetic Resonance Imaging

by Haseeb A. Khan, Yong-Kyu Lee, Mohammed Rafi Shaik, Sara T. Alrashood and Aishah A. Ekhzaimy

Int. J. Mol. Sci. 2022, 23(23), 15087; https://doi.org/10.3390/ijms232315087 - 1 Dec 2022

Cited by 9 | Viewed by 2206

Abstract

Cancer is a leading cause of death worldwide. Conventional methods of cancer treatment, including chemotherapy and radiotherapy, are associated with multiple side effects. Recently, photodynamic therapy (PDT) has emerged as an effective therapeutic modality for cancer treatment without adversely affecting normal tissue. In [...] Read more.

Cancer is a leading cause of death worldwide. Conventional methods of cancer treatment, including chemotherapy and radiotherapy, are associated with multiple side effects. Recently, photodynamic therapy (PDT) has emerged as an effective therapeutic modality for cancer treatment without adversely affecting normal tissue. In this study, we synthesized nitrogen doped graphene (NDG) and conjugated it with Mn₃O₄ nanoparticles to produce NDG-Mn₃O₄ nanocomposite with the aim of testing its bimodal performance including PDT and magnetic resonance imaging (MRI). We did not use any linker or binder for conjugation between NDG and Mn₃O₄, rather they were anchored by a milling process. The results of cell viability analysis showed that NDG-Mn₃O₄ nanocomposites caused significant cell death under laser irradiation, while control and Mn₃O₄ nanoparticles showed negligible cell death. We observed increased generation of singlet oxygen after exposure of NDG-Mn₃O₄ nanocomposites, which was directly proportional to the duration of laser irradiation. The results of MRI showed concentration dependent enhancement of signal intensity with an increasing concentration of NDG-Mn₃O₄ nanocomposites. In conclusion, NDG-Mn₃O₄ nanocomposites did not cause any cytotoxicity under physiological conditions. However, they produced significant and dose-dependent cytotoxicity in cancer cells after laser irradiation. NDG-Mn₃O₄ nanocomposites also exhibited concentration-dependent MRI contrast property, suggesting their possible application for cancer imaging. Further studies are warranted to test the theranostic potential of NDG-Mn₃O₄ nanocomposites using animal models of cancer. Full article

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19 pages, 6239 KiB

Open AccessArticle

Enhanced Acetaminophen Electrochemical Sensing Based on Nitrogen-Doped Graphene

by Lidia Magerusan, Florina Pogacean and Stela Pruneanu

Int. J. Mol. Sci. 2022, 23(23), 14866; https://doi.org/10.3390/ijms232314866 - 28 Nov 2022

Cited by 8 | Viewed by 2404

Abstract

Because of the widespread acetaminophen usage and the danger of harmful overdosing effects, developing appropriate procedures for its quantitative and qualitative assay has always been an intriguing and fascinating problem. A quick, inexpensive, and environmentally friendly approach based on direct voltage anodic graphite [...] Read more.

Because of the widespread acetaminophen usage and the danger of harmful overdosing effects, developing appropriate procedures for its quantitative and qualitative assay has always been an intriguing and fascinating problem. A quick, inexpensive, and environmentally friendly approach based on direct voltage anodic graphite rod exfoliation in the presence of inorganic salt aqueous solution ((NH₄)₂SO₄–0.3 M) has been established for the preparation of nitrogen-doped graphene (exf-NGr). The XRD analysis shows that the working material appears as a mixture of few (76.43%) and multi-layers (23.57%) of N-doped graphenes. From XPS, the C/O ratio was calculated to be 0.39, indicating a significant number of structural defects and the existence of multiple oxygen-containing groups at the surface of graphene sheets caused by heteroatom doping. Furthermore, the electrochemical performances of glassy carbon electrodes (GCEs) modified with exf-NGr for acetaminophen (AMP) detection and quantification have been assessed. The exf-NGr/GCE-modified electrode shows excellent reproducibility, stability, and anti-interfering characteristics with improved electrocatalytic activity over a wide detection range (0.1–100 µM), with a low limit for AMP detection (LOD = 3.03 nM). In addition, the developed sensor has been successfully applied in real sample analysis for the AMP quantification from different commercially available pharmaceutical formulations. Full article

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17 pages, 3441 KiB

Open AccessArticle

Effect of Cross-Linking Cations on In Vitro Biocompatibility of Apple Pectin Gel Beads

by Sergey Popov, Nikita Paderin, Elizaveta Chistiakova, Dmitry Ptashkin and Pavel A. Markov

Int. J. Mol. Sci. 2022, 23(23), 14789; https://doi.org/10.3390/ijms232314789 - 26 Nov 2022

Cited by 8 | Viewed by 2111

Abstract

The study aimed to compare the in vitro biocompatibility of pectin gels formed by different cross-linking cations. Hydrogel beads named CaPG, ZnPG, FePG, and AlPG were prepared from 4% solutions of apple pectin using ionotropic gelling with CaCl₂, ZnCl₂, [...] Read more.

The study aimed to compare the in vitro biocompatibility of pectin gels formed by different cross-linking cations. Hydrogel beads named CaPG, ZnPG, FePG, and AlPG were prepared from 4% solutions of apple pectin using ionotropic gelling with CaCl₂, ZnCl₂, FeCl₃, and AlCl₃, respectively. Cations influenced the gel strength of the wet gel beads in the following order (least strong) Ca²⁺ < Zn²⁺ < Fe³⁺~Al³⁺ (most strong). The swelling degree of the CaPG beads after 24 h of incubation in the RPMI-1640 medium was 104%, whereas the ZnPG, FePG, and AlPG beads swelled by 76, 108, and 134%, respectively. The strength of the pectin gel decreased significantly after incubation in the RPMI-1640 medium for 24 h, regardless of the cross-linking cation, although the FePG beads remained the strongest. All the pectin beads adsorbed serum proteins to a low degree, however the serum protein adsorption by the ZnPG and FePG beads (1.46 ± 0.87 and 1.35 ± 0.19 µg/mm²) was more than the CaPG and AlPG beads (0.31 ± 0.36 and 0.44 ± 0.25 µg/mm²). All the pectin beads reduced the production of TNF-α and IL-10 by hPBMCs in response to LPS stimulation. The IL-1β response of cells to LPS was significantly reduced by the CaPG, ZnPG, and FePG beads, whereas the AlPG beads enhanced it twofold. The CaPG, FePG, and AlPG beads had no cytotoxicity. The viability of hPBMCs and human fibroblasts incubated with ZnPG beads was 5.3 and 7.2%, respectively. Thus, the use of different cross-linking cations changed the properties of the pectin gel, which is important for biocompatibility. Full article

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22 pages, 11475 KiB

Open AccessArticle

Solid Solutions of Lindbergite–Glushinskite Series: Synthesis, Ionic Substitutions, Phase Transformation and Crystal Morphology

by Anatolii V. Korneev, Alina R. Izatulina, Mariya A. Kuz’mina and Olga V. Frank-Kamenetskaya

Int. J. Mol. Sci. 2022, 23(23), 14734; https://doi.org/10.3390/ijms232314734 - 25 Nov 2022

Cited by 1 | Viewed by 1735

Abstract

To clarify the crystal chemical features of natural and synthetic oxalates Me²⁺(C₂O₄)∙2H₂O (Me²⁺ = Fe, Mn, Mg, Zn), including minerals of the humboldtine group, solid solutions of lindbergite Mn(C₂O₄)∙2H [...] Read more.

To clarify the crystal chemical features of natural and synthetic oxalates Me²⁺(C₂O₄)∙2H₂O (Me²⁺ = Fe, Mn, Mg, Zn), including minerals of the humboldtine group, solid solutions of lindbergite Mn(C₂O₄)∙2H₂O–glushinskite Mg(C₂O₄)∙2H₂O were precipitated under various conditions, close to those characteristic of mineralization in biofilms: at the stoichiometric ratios ((Mn + Mg)/C₂O₄ = 1) and non-stochiometric ratios ((Mn + Mg)/C₂O₄ < 1), in the presence and absence of citrate ions. Investigation of precipitates was carried out by powder X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Thermodynamic modelling was performed in order to evaluate the lindbergite–glushinskite equilibrium. It was shown that glushinskite belongs to the orthorhombic β-modification (sp. Gr. Fddd), while lindbergite has a monoclinic α-modification (sp. gr. C2/c). Mg ions incorporate lindbergite in much higher quantities than Mn ions incorporate glushinskite; moreover, Mn glushinskites are characterized by violations of long-range order in their crystal structure. Lindbergite–glushinskite transition occurs abruptly and can be classified as a first-order isodimorphic transition. The Me²⁺/C₂O₄ ratio and the presence of citric acid in the solution affect the isomorphic capacity of lindbergite and glushinskite, the width of the transition and the equilibrium Mg/Mn ratio. The transition is accompanied by continuous morphological changes in crystals and crystal intergrowths. Given the obtained results, it is necessary to take into account in biotechnologies aimed at the bioremediation/bioleaching of metals from media containing mixtures of cations (Mg, Mn, Fe, Zn). Full article

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15 pages, 2162 KiB

Open AccessArticle

A Challenge toward Novel Quaternary Sulfides SrLnCuS₃ (Ln = La, Nd, Tm): Unraveling Synthetic Pathways, Structures and Properties

by Anna V. Ruseikina, Maxim V. Grigoriev, Leonid A. Solovyov, Vladimir A. Chernyshev, Aleksandr S. Aleksandrovsky, Alexander S. Krylov, Svetlana N. Krylova, Nikolai P. Shestakov, Dmitriy A. Velikanov, Alexander A. Garmonov, Alexey V. Matigorov, Marcel A. Eberle, Thomas Schleid and Damir A. Safin

Int. J. Mol. Sci. 2022, 23(20), 12438; https://doi.org/10.3390/ijms232012438 - 18 Oct 2022

Cited by 10 | Viewed by 3078

Abstract

We report on the novel heterometallic quaternary sulfides SrLnCuS₃ (Ln = La, Nd, Tm), obtained as both single crystals and powdered samples. The structures of both the single crystal and powdered samples of SrLaCuS₃ and SrNdCuS₃ belong to the orthorhombic [...] Read more.

We report on the novel heterometallic quaternary sulfides SrLnCuS₃ (Ln = La, Nd, Tm), obtained as both single crystals and powdered samples. The structures of both the single crystal and powdered samples of SrLaCuS₃ and SrNdCuS₃ belong to the orthorhombic space group Pnma but are of different structural types, while both samples of SrTmCuS₃ crystallize in the orthorhombic space group Cmcm with the structural type KZrCuS₃. Three-dimensional crystal structures of SrLaCuS₃ and SrNdCuS₃ are formed from the (Sr/Ln)S₇ capped trigonal prisms and CuS₄ tetrahedra. In SrLaCuS₃, alternating 2D layers are stacked, while the main backbone of the structure of SrNdCuS₃ is a polymeric 3D framework [(Sr/Ln)S₇]_n, strengthened by 1D polymeric chains (CuS₄)_n with 1D channels, filled by the other Sr²⁺/Ln³⁺ cations, which, in turn, form 1D dimeric ribbons. A 3D crystal structure of SrTmCuS₃ is constructed from the SrS₆ trigonal prisms, TmS₆ octahedra and CuS₄ tetrahedra. The latter two polyhedra are packed together into 2D layers, which are separated by 1D chains (SrS₆)_n and 1D free channels. In both crystal structures of SrLaCuS₃ obtained in this work, the crystallographic positions of strontium and lanthanum were partially mixed, while only in the structure of SrNdCuS₃, solved from the powder X-ray diffraction data, were the crystallographic positions of strontium and neodymium partially mixed. Band gaps of SrLnCuS₃ (Ln = La, Nd, Tm) were found to be 1.86, 1.94 and 2.57 eV, respectively. Both SrNdCuS₃ and SrTmCuS₃ were found to be paramagnetic at 20–300 K, with the experimental magnetic characteristics being in good agreement with the corresponding calculated parameters. Full article

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10 pages, 1318 KiB

Open AccessArticle

Experimental Study of the Impact of Trace Amounts of Acetylene and Methylacetylene on the Synthesis, Mechanical and Thermal Properties of Polypropylene

by Joaquín Hernández-Fernández, Ricardo Vivas-Reyes and Carlos A. T. Toloza

Int. J. Mol. Sci. 2022, 23(20), 12148; https://doi.org/10.3390/ijms232012148 - 12 Oct 2022

Cited by 21 | Viewed by 2130

Abstract

During the production of polymer-grade propylene, different processes are used to purify this compound and ensure that it is of the highest quality. However, some impurities such as acetylene and methyl acetylene are difficult to remove, and some of these impurities may be [...] Read more.

During the production of polymer-grade propylene, different processes are used to purify this compound and ensure that it is of the highest quality. However, some impurities such as acetylene and methyl acetylene are difficult to remove, and some of these impurities may be present in the propylene used to obtain polypropylene, which may have repercussions on the process. This study evaluates the impact of these acetylene and methyl acetylene impurities on the productivity of the polypropylene synthesis process and on the mechanical and thermal properties of the material obtained through the synthesis of eight samples with different concentrations of acetylene and eight samples with different concentrations of acetylene. We discovered that for the first concentrations of both acetylene (2 and 3 ppm) and methyl acetylene (0.03 and 0.1), the MFI, thermal recording, and mechanical properties of the resin were unaffected by the variation of the fluidity index, thermal degradation by TGA, and mechanical properties such as resistance to tension, bending, and impact. However, when the concentration exceeded 14 ppm for methyl acetylene and 12 ppm for acetylene, the resistance of this resin began to decrease linearly. Regarding production, this was affected by the first traces of acetylene and methyl acetylene progressively decreasing. Full article

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24 pages, 2345 KiB

Open AccessReview

Sodium Alginate—Natural Microencapsulation Material of Polymeric Microparticles

by Olimpia Daniela Frent, Laura Gratiela Vicas, Narcis Duteanu, Claudia Mona Morgovan, Tunde Jurca, Annamaria Pallag, Mariana Eugenia Muresan, Sanda Monica Filip, Roxana-Liana Lucaciu and Eleonora Marian

Int. J. Mol. Sci. 2022, 23(20), 12108; https://doi.org/10.3390/ijms232012108 - 11 Oct 2022

Cited by 62 | Viewed by 6912

Abstract

From the multitude of materials currently available on the market that can be used in the development of microparticles, sodium alginate has become one of the most studied natural anionic polymers that can be included in controlled-release pharmaceutical systems alongside other polymers due [...] Read more.

From the multitude of materials currently available on the market that can be used in the development of microparticles, sodium alginate has become one of the most studied natural anionic polymers that can be included in controlled-release pharmaceutical systems alongside other polymers due to its low cost, low toxicity, biocompatibility, biodegradability and gelatinous die-forming capacity in the presence of Ca²⁺ ions. In this review, we have shown that through coacervation, the particulate systems for the dispensing of drugs consisting of natural polymers are nontoxic, allowing the repeated administration of medicinal substances and the protection of better the medicinal substances from degradation, which can increase the capture capacity of the drug and extend its release from the pharmaceutical form. Full article

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10 pages, 826 KiB

Open AccessArticle

Iron Oxide Powder as Responsible for the Generation of Industrial Polypropylene Waste and as a Co-Catalyst for the Pyrolysis of Non-Additive Resins

by Joaquín Hernández-Fernández, John R. Castro-Suarez and Carlos A. T. Toloza

Int. J. Mol. Sci. 2022, 23(19), 11708; https://doi.org/10.3390/ijms231911708 - 3 Oct 2022

Cited by 20 | Viewed by 2424

Abstract

For the synthesis of polymeric resins, it is of great importance to review the raw materials and the equipment to be used to avoid the presence of compounds that may affect the effectiveness of the polymerization and the characteristics of the plastic to [...] Read more.

For the synthesis of polymeric resins, it is of great importance to review the raw materials and the equipment to be used to avoid the presence of compounds that may affect the effectiveness of the polymerization and the characteristics of the plastic to be obtained. Iron oxide is a compound that can be present in reactors after maintenance due to the techniques used and the cleaning of this equipment, and it can affect the characteristics of the resins, reducing their quality. In this study, the presence of FeO in different concentrations was evaluated to determine its effects on the properties and pyrolysis of polypropylene resins by using X-ray refraction to determine the elements of the samples, evaluating thermal degradation by TGA, the variation in molecular weight by measuring the MFI, and the compounds obtained from pyrolysis by chromatography. The results showed that the thermal degradation decreased as the FeO concentration increased, while for the MFI, the relationship was directly proportional. The evaluation of the compounds obtained from pyrolysis showed an increase in the production of alcohols, alkynes, ketones, and acids, and a decrease in alkanes and alkenes, showing that FeO affects the properties of polypropylene and the compounds that are produced during pyrolysis. Full article

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17 pages, 10130 KiB

Open AccessArticle

Synthesis of M-Ag₃PO₄, (M = Se, Ag, Ta) Nanoparticles and Their Antibacterial and Cytotoxicity Study

by Faiza Qureshi, Muhammad Nawaz, Mohammad Azam Ansari, Firdos Alam Khan, Mahmoud M. Berekaa, Samar A. Abubshait, Rayyanah Al-Mutairi, Alok K. Paul, Veeranoot Nissapatorn, Maria de Lourdes Pereira and Polrat Wilairatana

Int. J. Mol. Sci. 2022, 23(19), 11403; https://doi.org/10.3390/ijms231911403 - 27 Sep 2022

Cited by 11 | Viewed by 3540

Abstract

Silver Phosphate, Ag₃PO₄, being a highly capable clinical molecule, an ultrasonic method was employed to synthesize the M-Ag₃PO_4, (M = Se, Ag, Ta) nanoparticles which were evaluated for antibacterial and cytotoxicity activities post-characterization. Escherichia coli and [...] Read more.

Silver Phosphate, Ag₃PO₄, being a highly capable clinical molecule, an ultrasonic method was employed to synthesize the M-Ag₃PO_4, (M = Se, Ag, Ta) nanoparticles which were evaluated for antibacterial and cytotoxicity activities post-characterization. Escherichia coli and Staphylococcus aureus were used for antibacterial testing and the effects of sonication on bacterial growth with sub-MIC values of M-Ag₃PO₄ nanoparticles were examined. The effect of M-Ag₃PO₄ nanoparticles on human colorectal carcinoma cells (HCT-116) and human cervical carcinoma cells (HeLa cells) was examined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay and DAPI (4′,6-diamidino-2-phenylindole) staining. Additionally, we analyzed the effect of nanoparticles on normal and non-cancerous human embryonic kidney cells (HEK-293). Ag-Ag₃PO₄ exhibited enhanced antibacterial activity followed by Ta-Ag₃PO_4, Ag₃PO₄, and Se-Ag₃PO₄ nanoparticles against E. coli. Whereas the order of antibacterial activity against Staphylococcus aureus was Ag₃PO₄ > Ag-Ag₃PO₄ > Ta-Ag₃PO₄ > Se-Ag₃PO₄, respectively. Percentage inhibition of E. coli was 98.27, 74.38, 100, and 94.2%, while percentage inhibition of S. aureus was 25.53, 80.28, 99.36, and 20.22% after treatment with Ag₃PO₄, Se-Ag₃PO₄, Ag-Ag₃PO₄, and Ta-Ag₃PO_4, respectively. The MTT assay shows a significant decline in the cell viability after treating with M-Ag₃PO₄ nanoparticles. The IC₅₀ values for Ag₃PO_4, Se-Ag₃PO_4, Ag-Ag₃PO₄, and Ta-Ag₃PO₄ on HCT-116 were 39.44, 28.33, 60.24, 58.34 µg/mL; whereas for HeLa cells, they were 65.25, 61.27, 75.52, 72.82 µg/mL, respectively. M-Ag₃PO₄ nanoparticles did not inhibit HEK-293 cells. Apoptotic assay revealed that the numbers of DAPI stained cells were significantly lower in the M-Ag₃PO₄-treated cells versus control. Full article

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12 pages, 3995 KiB

Open AccessArticle

Effect of Pt Decoration on the Optical Properties of Pristine and Defective MoS₂: An Ab-Initio Study

by Juan Manuel Ramírez-de-Arellano, Ali Fransuani Jiménez-González, Mónica Canales and Luis Fernando Magaña

Int. J. Mol. Sci. 2022, 23(19), 11199; https://doi.org/10.3390/ijms231911199 - 23 Sep 2022

Cited by 2 | Viewed by 2165

Abstract

Using structural relaxation calculations and first-principles molecular dynamics (FPMD), we performed numerical simulations to explore the interaction of a 2D MoS₂ surface and a platinum atom, calculating the optical properties of the resulting material. We explored three initial positions for the interaction [...] Read more.

Using structural relaxation calculations and first-principles molecular dynamics (FPMD), we performed numerical simulations to explore the interaction of a 2D MoS₂ surface and a platinum atom, calculating the optical properties of the resulting material. We explored three initial positions for the interaction of the Pt atom and the pristine MoS₂ surface, plus another position between Pt and the MoS₂ surface with a sulfur vacancy V_S. The surface absorbed the Pt atom in all cases considered, with absorption energies ranging from −2.77 eV to −5.83 eV. We calculated the optical properties and band structure of the two cases with the largest absorption energies (−3.45 eV and −5.83 eV). The pristine MoS₂ is a semiconductor with a gap of around 1.80 eV. With the adsorption of the Pt atom (the −3.45 eV case), the material reduces its band gap to 0.95 eV. Additionally, the optical absorption in the visible range is greatly increased. The energy band structure of the 2D MoS₂ with a sulfur vacancy V_S shows a band gap of 0.74 eV, with consequent changes in its optical properties. After the adsorption of Pt atoms in the V_S vacancy, the material has a band gap of 1.06 eV. In this case, the optical absorption in the visible range increases by about eight times. The reflectivity in the infrared range gets roughly doubled for both situations of the Pt-absorbed atom considered. Finally, we performed two FPMD runs at 300 K to test the stability of the cases with the lowest and highest absorption energies observed, confirming the qualitative results obtained with the structural relaxations. Full article

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22 pages, 6532 KiB

Open AccessArticle

Spontaneous Transformation of Biomedical Polymeric Silver Salt into a Nanocomposite: Physical–Chemical and Antimicrobial Properties Dramatically Depend on the Initial Preparation State

by Klavdia A. Abzaeva, Boris G. Sukhov, Spartak S. Khutsishvili, Elena B. Tarabukina, Lev E. Zelenkov, Anna V. Nevezhina and Tat’yana V. Fadeeva

Int. J. Mol. Sci. 2022, 23(18), 10963; https://doi.org/10.3390/ijms231810963 - 19 Sep 2022

Viewed by 2721

Abstract

An antimicrobial polyacrylic silver salt (freshly prepared, stored for one year and model-aged) was studied by physical–chemical techniques for nanoparticle detection. In all cases, this salt represents a composite of radical-enriched macromolecules and silver(0) nanoparticles. As time passed, the initial small spherical nanoparticles [...] Read more.

An antimicrobial polyacrylic silver salt (freshly prepared, stored for one year and model-aged) was studied by physical–chemical techniques for nanoparticle detection. In all cases, this salt represents a composite of radical-enriched macromolecules and silver(0) nanoparticles. As time passed, the initial small spherical nanoparticles were converted into larger non-spherical silver nanoparticles. The initial highly water-soluble antimicrobial solid nanocomposite almost loses its solubility in water and cannot be used as an antimicrobial agent. Unlike insoluble solid silver polyacrylate, its freshly prepared aqueous solution retains a liquid-phase consistency after one year as well as pronounced antimicrobial properties. The mechanism of these spontaneous and model-simulated processes was proposed. These results have attracted attention for officinal biomedicinal silver salts as complex radical-enriched nanocomposite substances; they also indicate contrasting effects of silver polymeric salt storing in solid and solution forms that dramatically influence antimicrobial activity. Full article

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14 pages, 3050 KiB

Open AccessArticle

Effects of Various Disinfection Methods on the Material Properties of Silicone Dental Impressions of Different Types and Viscosities

by Joanna Wezgowiec, Anna Paradowska-Stolarz, Andrzej Malysa, Sylwia Orzeszek, Piotr Seweryn and Mieszko Wieckiewicz

Int. J. Mol. Sci. 2022, 23(18), 10859; https://doi.org/10.3390/ijms231810859 - 17 Sep 2022

Cited by 21 | Viewed by 2998

Abstract

There is an ongoing search for novel disinfection techniques that are not only effective, cheap, and convenient, but that also do not have adverse effects on the properties of dental impressions. We compared the effects of various methods (UVC, gaseous ozone, commercial solution, [...] Read more.

There is an ongoing search for novel disinfection techniques that are not only effective, cheap, and convenient, but that also do not have adverse effects on the properties of dental impressions. We compared the effects of various methods (UVC, gaseous ozone, commercial solution, and spray) on the dimensional change, tensile strength, and hardness of silicone impressions. Moreover, as a secondary aim, we performed a statistical comparison of the properties of nondisinfected addition (Panasil Putty Soft, Panasil monophase Medium, Panasil initial contact Light) and condensation silicones (Zetaplus Putty and Oranwash L), as well as a comparison of materials of various viscosities (putty, medium-bodied, and light-bodied). Our results revealed that addition silicones had higher dimensional stability, tensile strength, and Shore A hardness compared to condensation silicones. Both traditional (immersion and spraying) and alternative methods of disinfection (UVC and ozone) had no significant impact on the tensile properties and dimensional stability of the studied silicones; however, they significantly affected the hardness, particularly of Oranwash L. Our study demonstrated that, similarly to standard liquid disinfectants, both UVC and ozone do not strongly affect the material properties of most silicones. However, before recommendation, their usefulness for each individual material should be thoroughly evaluated. Full article

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23 pages, 5617 KiB

Open AccessArticle

Disclosing the Biocide Activity of α-Ag_2−2xCu_xWO₄ (0 ≤ x ≤ 0.16) Solid Solutions

by Paula Fabiana dos Santos Pereira, Camila Cristina De Foggi, Amanda Fernandes Gouveia, Ivo Mateus Pinatti, Luís Antônio Cabral, Eva Guillamon, Iván Sorribes, Miguel A. San-Miguel, Carlos Eduardo Vergani, Alexandre Zirpoli Simões, Edison Z. da Silva, Laécio Santos Cavalcante, Rosa Llusar, Elson Longo and Juan Andrés

Int. J. Mol. Sci. 2022, 23(18), 10589; https://doi.org/10.3390/ijms231810589 - 13 Sep 2022

Cited by 4 | Viewed by 2256

Abstract

In this work, α-Ag_2−2xCu_xWO₄ (0 ≤ x ≤ 0.16) solid solutions with enhanced antibacterial (against methicillin-resistant Staphylococcus aureus) and antifungal (against Candida albicans) activities are reported. A plethora of techniques (X-ray diffraction with Rietveld refinements, [...] Read more.

In this work, α-Ag_2−2xCu_xWO₄ (0 ≤ x ≤ 0.16) solid solutions with enhanced antibacterial (against methicillin-resistant Staphylococcus aureus) and antifungal (against Candida albicans) activities are reported. A plethora of techniques (X-ray diffraction with Rietveld refinements, inductively coupled plasma atomic emission spectrometry, micro-Raman spectroscopy, attenuated total reflectance–Fourier transform infrared spectroscopy, field emission scanning electron microscopy, ultraviolet–visible spectroscopy, photoluminescence emissions, and X-ray photoelectron spectroscopy) were employed to characterize the as-synthetized samples and determine the local coordination geometry of Cu²⁺ cations at the orthorhombic lattice. To find a correlation between morphology and biocide activity, the experimental results were sustained by first-principles calculations at the density functional theory level to decipher the cluster coordinations and electronic properties of the exposed surfaces. Based on the analysis of the under-coordinated Ag and Cu clusters at the (010) and (101) exposed surfaces, we propose a mechanism to explain the biocide activity of these solid solutions. Full article

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25 pages, 3081 KiB

Open AccessReview

Progress of Nanomaterials-Based Photothermal Therapy for Oral Squamous Cell Carcinoma

by Qin Niu, Qiannan Sun, Rushui Bai, Yunfan Zhang, Zimeng Zhuang, Xin Zhang, Tianyi Xin, Si Chen and Bing Han

Int. J. Mol. Sci. 2022, 23(18), 10428; https://doi.org/10.3390/ijms231810428 - 9 Sep 2022

Cited by 19 | Viewed by 3973

Abstract

Oral squamous cell carcinoma (OSCC) is one of the top 15 most prevalent cancers worldwide. However, the current treatment models for OSCC (e.g., surgery, chemotherapy, radiotherapy, and combination therapy) present several limitations: damage to adjacent healthy tissue, possible recurrence, low efficiency, and severe [...] Read more.

Oral squamous cell carcinoma (OSCC) is one of the top 15 most prevalent cancers worldwide. However, the current treatment models for OSCC (e.g., surgery, chemotherapy, radiotherapy, and combination therapy) present several limitations: damage to adjacent healthy tissue, possible recurrence, low efficiency, and severe side effects. In this context, nanomaterial-based photothermal therapy (PTT) has attracted extensive research attention. This paper reviews the latest progress in the application of biological nanomaterials for PTT in OSCC. We divide photothermal nanomaterials into four categories (noble metal nanomaterials, carbon-based nanomaterials, metal compounds, and organic nanomaterials) and introduce each category in detail. We also mention in detail the drug delivery systems for PTT of OSCC and briefly summarize the applications of hydrogels, liposomes, and micelles. Finally, we note the challenges faced by the clinical application of PTT nanomaterials and the possibility of further improvement, providing direction for the future research of PTT in OSCC treatment. Full article

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27 pages, 4530 KiB

Open AccessReview

Extraction of High-Value Chemicals from Plants for Technical and Medical Applications

by Pritam Kapadia, Amy S. Newell, John Cunningham, Michael R. Roberts and John G. Hardy

Int. J. Mol. Sci. 2022, 23(18), 10334; https://doi.org/10.3390/ijms231810334 - 7 Sep 2022

Cited by 41 | Viewed by 12823

Abstract

Plants produce a variety of high-value chemicals (e.g., secondary metabolites) which have a plethora of biological activities, which may be utilised in many facets of industry (e.g., agrisciences, cosmetics, drugs, neutraceuticals, household products, etc.). Exposure to various different environments, as well as their [...] Read more.

Plants produce a variety of high-value chemicals (e.g., secondary metabolites) which have a plethora of biological activities, which may be utilised in many facets of industry (e.g., agrisciences, cosmetics, drugs, neutraceuticals, household products, etc.). Exposure to various different environments, as well as their treatment (e.g., exposure to chemicals), can influence the chemical makeup of these plants and, in turn, which chemicals will be prevalent within them. Essential oils (EOs) usually have complex compositions (>300 organic compounds, e.g., alkaloids, flavonoids, phenolic acids, saponins and terpenes) and are obtained from botanically defined plant raw materials by dry/steam distillation or a suitable mechanical process (without heating). In certain cases, an antioxidant may be added to the EO (EOs are produced by more than 17,500 species of plants, but only ca. 250 EOs are commercially available). The interesting bioactivity of the chemicals produced by plants renders them high in value, motivating investment in their production, extraction and analysis. Traditional methods for effectively extracting plant-derived biomolecules include cold pressing and hydro/steam distillation; newer methods include solvent/Soxhlet extractions and sustainable processes that reduce waste, decrease processing times and deliver competitive yields, examples of which include microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), subcritical water extraction (SWE) and supercritical CO₂ extraction (scCO₂). Once extracted, analytical techniques such as chromatography and mass spectrometry may be used to analyse the contents of the high-value extracts within a given feedstock. The bioactive components, which can be used in a variety of formulations and products (e.g., displaying anti-aging, antibacterial, anticancer, anti-depressive, antifungal, anti-inflammatory, antioxidant, antiparasitic, antiviral and anti-stress properties), are biorenewable high-value chemicals. Full article

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20 pages, 3369 KiB

Open AccessArticle

Amorphous and Co-Amorphous Olanzapine Stability in Formulations Intended for Wet Granulation and Pelletization

by Nuno F. da Costa, Rolf Daniels, Ana I. Fernandes and João F. Pinto

Int. J. Mol. Sci. 2022, 23(18), 10234; https://doi.org/10.3390/ijms231810234 - 6 Sep 2022

Cited by 4 | Viewed by 2550

Abstract

The preparation of amorphous and co-amorphous systems (CAMs) effectively addresses the solubility and bioavailability issues of poorly water-soluble chemical entities. However, stress conditions imposed during common pharmaceutical processing (e.g., tableting) may cause the recrystallization of the systems, warranting close stability monitoring throughout production. [...] Read more.

The preparation of amorphous and co-amorphous systems (CAMs) effectively addresses the solubility and bioavailability issues of poorly water-soluble chemical entities. However, stress conditions imposed during common pharmaceutical processing (e.g., tableting) may cause the recrystallization of the systems, warranting close stability monitoring throughout production. This work aimed at assessing the water and heat stability of amorphous olanzapine (OLZ) and OLZ-CAMs when subject to wet granulation and pelletization. Starting materials and products were characterized using calorimetry, diffractometry and spectroscopy, and their performance behavior was evaluated by dissolution testing. The results indicated that amorphous OLZ was reconverted back to a crystalline state after exposure to water and heat; conversely, OLZ-CAMs stabilized with saccharin (SAC), a sulfonic acid, did not show any significant loss of the amorphous content, confirming the higher stability of OLZ in the CAM. Besides resistance under the processing conditions of the dosage forms considered, OLZ-CAMs presented a higher solubility and dissolution rate than the respective crystalline counterpart. Furthermore, in situ co-amorphization of OLZ and SAC during granule production with high fractions of water unveils the possibility of reducing production steps and associated costs. Full article

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17 pages, 3982 KiB

Open AccessArticle

Medical Use of Polycatecholamines + Oxidoreductases-Modified Curdlan Hydrogels—Perspectives

by Anna Michalicha, Agata Przekora, Dawid Stefaniuk, Magdalena Jaszek, Anna Matuszewska and Anna Belcarz

Int. J. Mol. Sci. 2022, 23(17), 10084; https://doi.org/10.3390/ijms231710084 - 3 Sep 2022

Cited by 3 | Viewed by 2259

Abstract

Curdlan (β-1,3-glucan), as a biodegradable polymer, is still an underestimated but potentially attractive matrix for the production of dressing materials. However, due to its lack of susceptibility to functionalization, its use is limited. The proposed curdlan modification, using a functional polycatecholamine layer, enables [...] Read more.

Curdlan (β-1,3-glucan), as a biodegradable polymer, is still an underestimated but potentially attractive matrix for the production of dressing materials. However, due to its lack of susceptibility to functionalization, its use is limited. The proposed curdlan modification, using a functional polycatecholamine layer, enables the immobilization of selected oxidoreductases (laccase and peroxidase) on curdlan hydrogel. The following significant changes of biological and mechanical properties of polycatecholamines + oxidoreductases-modified matrices were observed: reduced response of human monocytes in contact with the hydrogels, modulated reaction of human blood, in terms of hemolysis and clot formation, and changed mechanical properties. The lack of toxicity towards human fibroblasts and the suppression of cytokines released by human monocytes in comparison to pristine curdlan hydrogel, seems to make the application of such modifications attractive for biomedical purposes. The obtained results could also be useful for construction of a wide range of biomaterials based on other polymer hydrogels. Full article

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25 pages, 5431 KiB

Open AccessReview

Innovation of Imine Metal Chelates as Corrosion Inhibitors at Different Media: A Collective Study

by Hany M. Abd El-Lateef, Tarek El-Dabea, Mai M. Khalaf and Ahmed M. Abu-Dief

Int. J. Mol. Sci. 2022, 23(16), 9360; https://doi.org/10.3390/ijms23169360 - 19 Aug 2022

Cited by 15 | Viewed by 2726

Abstract

The corrosion inhibition of transition metal chelates derived from Schiff base ligands was tested for (mild, copper, stainless, aluminum and carbon) steel in various concentrations of (HCl, HNO₃ and H₂SO₄) acidic medium at 25 °C through (weight loss, [...] Read more.

The corrosion inhibition of transition metal chelates derived from Schiff base ligands was tested for (mild, copper, stainless, aluminum and carbon) steel in various concentrations of (HCl, HNO₃ and H₂SO₄) acidic medium at 25 °C through (weight loss, potentiodynamic polarization, polarization curves, electrochemical impedance spectroscopy (EIS) and open circuit potential measurements (OCP)) techniques. The studied compounds were identified with various spectral, analytical and physico-chemical techniques. It was observed that the investigated compounds had a significant inhibitory impact on the corrosion of diverse steels in the medium investigated. The analysis shows that increasing the dose of the studied complexes improves the corresponding inhibitory efficiency values. Negative results of Gibb’s free adsorption energy (

Δ G_{a d s}^{0}

) prove the suppression process’s spontaneous and physical adsorption, which contradicts the Langmuir adsorption isotherm. As a result of this insight, a novel bridge between nuclearity driven coordinated inorganic chemistry and materials, as well as corrosion control, has been built. This review provides an overview of the use of Schiff bases and associated transition metals as potential corrosion inhibitors, including the factors that influence their application. Full article

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10 pages, 2787 KiB

Open AccessArticle

NH₂-Functionalized Magnetic Nanoparticles for the N-Glycomic Analysis of Patients with Multiple Sclerosis

by Dalma Dojcsák, Ágnes Mária Ilosvai, László Vanyorek, Ibolya Gilányi, Csaba Oláh, László Horváth and Csaba Váradi

Int. J. Mol. Sci. 2022, 23(16), 9095; https://doi.org/10.3390/ijms23169095 - 13 Aug 2022

Cited by 1 | Viewed by 2089

Abstract

Glycosylation is vital for well-functioning glycoproteins and is reportedly altered in chronic inflammatory disorders, including multiple sclerosis (MS). High-throughput quantitative measurement of protein glycosylation is challenging, as glycans lack fluorophore groups and require fluorescent labeling. The attachment of fluorescent tags to each glycan [...] Read more.

Glycosylation is vital for well-functioning glycoproteins and is reportedly altered in chronic inflammatory disorders, including multiple sclerosis (MS). High-throughput quantitative measurement of protein glycosylation is challenging, as glycans lack fluorophore groups and require fluorescent labeling. The attachment of fluorescent tags to each glycan moiety necessitates sample clean-up for reliable quantitation. The use of magnetic particles in glycan sample preparation is reportedly an easy-to-use solution to accomplish large-scale biomarker discovery studies. In this study, NH₂-funtionalized magnetic nanoparticles were synthetized, characterized and applied for the glycosylation analysis of serum samples from patients diagnosed with multiple sclerosis and corresponding healthy controls. Serum samples were PNGase F digested and labeled by procainamide via reductive amination, followed by magnetic nanoparticle-based purification. The prepared samples were analyzed by hydrophilic interaction liquid chromatography, allowing for the relative quantitation of the individual glycan species. Significant glycosylation alterations were detected between MS patients and healthy controls, especially when analyzing the different gender groups. Full article

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2 pages, 162 KiB

Open AccessCorrection

Correction: Bok et al. Super-Toughened Fumed-Silica-Reinforced Thiol-Epoxy Composites Containing Epoxide-Terminated Polydimethylsiloxanes. Int. J. Mol. Sci. 2021, 22, 8097

by Goseong Bok, Gayoung Lim, Mingi Kwak and Youngmin Kim

Int. J. Mol. Sci. 2022, 23(15), 8545; https://doi.org/10.3390/ijms23158545 - 1 Aug 2022

Viewed by 1455

Abstract

The authors wish to make the following corrections to the original publication [...] Full article

18 pages, 1777 KiB

Open AccessReview

Biomedical Polyurethanes for Anti-Cancer Drug Delivery Systems: A Brief, Comprehensive Review

by Marcin Sobczak and Karolina Kędra

Int. J. Mol. Sci. 2022, 23(15), 8181; https://doi.org/10.3390/ijms23158181 - 25 Jul 2022

Cited by 27 | Viewed by 3481

Abstract

With the intensive development of polymeric biomaterials in recent years, research using drug delivery systems (DDSs) has become an essential strategy for cancer therapy. Various DDSs are expected to have more advantages in anti-neoplastic effects, including easy preparation, high pharmacology efficiency, low toxicity, [...] Read more.

With the intensive development of polymeric biomaterials in recent years, research using drug delivery systems (DDSs) has become an essential strategy for cancer therapy. Various DDSs are expected to have more advantages in anti-neoplastic effects, including easy preparation, high pharmacology efficiency, low toxicity, tumor-targeting ability, and high drug-controlled release. Polyurethanes (PUs) are a very important kind of polymers widely used in medicine, pharmacy, and biomaterial engineering. Biodegradable and non-biodegradable PUs are a significant group of these biomaterials. PUs can be synthesized by adequately selecting building blocks (a polyol, a di- or multi-isocyanate, and a chain extender) with suitable physicochemical and biological properties for applications in anti-cancer DDSs technology. Currently, there are few comprehensive reports on a summary of polyurethane DDSs (PU-DDSs) applied for tumor therapy. This study reviewed state-of-the-art PUs designed for anti-cancer PU-DDSs. We studied successful applications and prospects for further development of effective methods for obtaining PUs as biomaterials for oncology. Full article

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19 pages, 4790 KiB

Open AccessArticle

Green Blends Based on Ionic Liquids with Improved Performance for Membrane Technology: Perspectives for Environmental Applications

by Anca Filimon, Adina Maria Dobos, Oana Dumbrava, Florica Doroftei and Lavinia Lupa

Int. J. Mol. Sci. 2022, 23(14), 7961; https://doi.org/10.3390/ijms23147961 - 19 Jul 2022

Cited by 5 | Viewed by 2187

Abstract

Present research was directed towards the development of new high-performance and cost-effective polysulfone membranes (PSFQ) by introducing ionic liquids (ILs—Cyphos 101 IL and Aliquat 336) into their matrix. Variation of ILs was performed with the aim to find the one that brings new [...] Read more.

Present research was directed towards the development of new high-performance and cost-effective polysulfone membranes (PSFQ) by introducing ionic liquids (ILs—Cyphos 101 IL and Aliquat 336) into their matrix. Variation of ILs was performed with the aim to find the one that brings new properties and improves the functionality and selectivity of PSFQ membranes in ultrafiltration processes. Based on the obtained results of the rheological study, we established the compatibility of compounds and optimal content of the used ILs, namely 3 wt% and 15 wt% Cyphos 101 IL and compositions varying between 3 and 15 wt % Aliquat 336. Results indicated that the ILs acted as plasticizers when they were added to the system, a helpful aspect in processing membranes used in water decontamination. The efficiency and performance of the membranes were evaluated by their use in the treatment of diclofenac (DCF)-containing waters. Membranes obtained from PSFQ/Aliquat 336 solution containing 15 wt% IL exhibited a 97% removal degree of DCF in the treatment process of 50 mL solution containing 3 mg/L DCF. The separation efficiency was kept constant for four filtration/cleaning cycles. The results indicated an improvement in membrane performance as the amount of IL in their structure increased, which confirms the potential for application in water treatment processes. Full article

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17 pages, 7409 KiB

Open AccessArticle

Behavior of Ni20Cr Alloy in Molten Nitrate Salts

by Nestor Belisario Gomez-Guzman, Daniel Lopez-Dominguez, Cinthya Dinorah Arrieta-Gonzalez, Jan Mayen, Eduardo Porcayo-Palafox, Jose Guadalupe Chacon-Nava, Jose Gonzalo Gonzalez-Rodriguez, Jesus Porcayo-Calderon and Roberto Ademar Rodriguez-Diaz

Int. J. Mol. Sci. 2022, 23(14), 7895; https://doi.org/10.3390/ijms23147895 - 18 Jul 2022

Cited by 1 | Viewed by 2454

Abstract

This study reports the behavior of the Ni20Cr alloy in molten nitrate salts. Its behavior was evaluated in the eutectic mixture called Solar Salt (binary salt) and in a ternary mixture (90% Solar Salt and 10% lanthanum nitrate). The addition of lanthanum nitrate [...] Read more.

This study reports the behavior of the Ni20Cr alloy in molten nitrate salts. Its behavior was evaluated in the eutectic mixture called Solar Salt (binary salt) and in a ternary mixture (90% Solar Salt and 10% lanthanum nitrate). The addition of lanthanum nitrate was performed to determine if the presence of the La³⁺ cation could act as a corrosion inhibitor. Through mass loss and potentiodynamic polarization studies, the effects of both electrolytes on the corrosion resistance of the alloy at 300, 400, and 500 °C and at exposure times of 250, 500, 750, and 1000 h were determined. The results showed an increase in the corrosivity of the ternary salt, due to a decrease in its melting point and an increase in the concentration of nitrate ions. However, it was observed that the La³⁺ cations formed a protective layer (La₂O₃) on the alloy surface. In both corrosive media, the Ni20Cr alloy showed excellent corrosion resistance, due to its ability to form protective layers of Cr₂O₃, NiO, and NiCr₂O₄, in addition to the presence of a layer of La₂O₃ in the case of the ternary salt. Full article

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18 pages, 4059 KiB

Open AccessArticle

Structural Diversity of Mercury(II) Halide Complexes Containing Bis-pyridyl-bis-amide with Bulky and Angular Backbones: Ligand Effect and Metal Sensing

by Manivannan Govindaraj, Wei-Chun Huang, Chia-Yi Lee, Venkatesan Lakshmanan, Yu-Hsiang Liu, Pamela Berilyn So, Chia-Her Lin and Jhy-Der Chen

Int. J. Mol. Sci. 2022, 23(14), 7861; https://doi.org/10.3390/ijms23147861 - 16 Jul 2022

Cited by 6 | Viewed by 2298

Abstract

Hg(II) halide complexes [HgCl₂] 2L¹ [L¹ = N,N’-bis(3-pyridyl)bicyclo(2,2,2,)oct-7-ene-2,3,5,6-tetracarboxylic diamide), 1, [HgBr₂(L¹)]_n, 2, [HgI₂(L¹)], 3, [Hg₂X₄(L² [...] Read more.

Hg(II) halide complexes [HgCl₂] 2L¹ [L¹ = N,N’-bis(3-pyridyl)bicyclo(2,2,2,)oct-7-ene-2,3,5,6-tetracarboxylic diamide), 1, [HgBr₂(L¹)]_n, 2, [HgI₂(L¹)], 3, [Hg₂X₄(L²)₂] [X = Cl, 4, Br, 5, and I, 6; L² = N,N’-bis(4-pyridylmethyl)bicyclo(2,2,2,)oct-7-ene-2,3,5,6-tetracarboxylic diamide] and {[HgX₂(L³)]⋅H₂O}_n [X = Cl, 7, Br, 8 and I, 9; L³ = 4,4′-oxybis(N-(pyridine-3-yl)benzamide)] are reported and structurally characterized using single-crystal X-ray diffraction analyses. The linear HgCl₂ units of complex 1 are interlinked by the L¹ ligands through Hg---N and Hg---O interactions, resulting in 1D supramolecular chains. Complex 2 shows 1D zigzag chains interlinked through the Br---Br interactions to form 1D looped supramolecular chains, while the mononuclear [HgI₂L²] molecules of 3 are interlinked through Hg---O and I---I interactions, forming 2D supramolecular layers. Complexes 4–6 are isomorphous dinuclear metallocycles, and 7–9 form isomorphous 1D zigzag chains. The roles of the ligand type and the halide anion in determining the structural diversity of 1–9 is discussed and the luminescent properties of 7–9 evaluated. Complexes 7–9 manifest stability in aqueous environments. Moreover, complexes 7 and 8 show good sensing towards Fe³⁺ ions with low detection limits and good reusability up to five cycles, revealing that the Hg-X---Fe³⁺ (X = Cl and Br) interaction may have an important role in determining the quenching effect of 7 and 8. Full article

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27 pages, 11029 KiB

Open AccessReview

Insight and Recent Advances into the Role of Topography on the Cell Differentiation and Proliferation on Biopolymeric Surfaces

by Raluca Tudureanu, Iuliana M. Handrea-Dragan, Sanda Boca and Ioan Botiz

Int. J. Mol. Sci. 2022, 23(14), 7731; https://doi.org/10.3390/ijms23147731 - 13 Jul 2022

Cited by 23 | Viewed by 3374

Abstract

It is well known that surface topography plays an important role in cell behavior, including adhesion, migration, orientation, elongation, proliferation and differentiation. Studying these cell functions is essential in order to better understand and control specific characteristics of the cells and thus to [...] Read more.

It is well known that surface topography plays an important role in cell behavior, including adhesion, migration, orientation, elongation, proliferation and differentiation. Studying these cell functions is essential in order to better understand and control specific characteristics of the cells and thus to enhance their potential in various biomedical applications. This review proposes to investigate the extent to which various surface relief patterns, imprinted in biopolymer films or in polymeric films coated with biopolymers, by utilizing specific lithographic techniques, influence cell behavior and development. We aim to understand how characteristics such as shape, dimension or chemical functionality of surface relief patterns alter the orientation and elongation of cells, and thus, finally make their mark on the cell proliferation and differentiation. We infer that such an insight is a prerequisite for pushing forward the comprehension of the methodologies and technologies used in tissue engineering applications and products, including skin or bone implants and wound or fracture healing. Full article

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16 pages, 1605 KiB

Open AccessArticle

Tracking Prostate Carcinogenesis over Time through Urine Proteome Profiling in an Animal Model: An Exploratory Approach

by Alexandra Moreira-Pais, Rita Nogueira-Ferreira, Stephanie Reis, Susana Aveiro, António Barros, Tânia Melo, Bárbara Matos, José Alberto Duarte, Fernanda Seixas, Pedro Domingues, Francisco Amado, Margarida Fardilha, Paula A. Oliveira, Rita Ferreira and Rui Vitorino

Int. J. Mol. Sci. 2022, 23(14), 7560; https://doi.org/10.3390/ijms23147560 - 8 Jul 2022

Cited by 1 | Viewed by 2720

Abstract

Prostate cancer (PCa) is one of the most lethal diseases in men, which justifies the search for new diagnostic tools. The aim of the present study was to gain new insights into the progression of prostate carcinogenesis by analyzing the urine proteome. To [...] Read more.

Prostate cancer (PCa) is one of the most lethal diseases in men, which justifies the search for new diagnostic tools. The aim of the present study was to gain new insights into the progression of prostate carcinogenesis by analyzing the urine proteome. To this end, urine from healthy animals and animals with prostate adenocarcinoma was analyzed at two time points: 27 and 54 weeks. After 54 weeks, the incidence of pre-neoplastic and neoplastic lesions in the PCa animals was 100%. GeLC-MS/MS and subsequent bioinformatics analyses revealed several proteins involved in prostate carcinogenesis. Increased levels of retinol-binding protein 4 and decreased levels of cadherin-2 appear to be characteristic of early stages of the disease, whereas increased levels of enolase-1 and T-kininogen 2 and decreased levels of isocitrate dehydrogenase 2 describe more advanced stages. With increasing age, urinary levels of clusterin and corticosteroid-binding globulin increased and neprilysin levels decreased, all of which appear to play a role in prostate hyperplasia or carcinogenesis. The present exploratory analysis can be considered as a starting point for studies targeting specific human urine proteins for early detection of age-related maladaptive changes in the prostate that may lead to cancer. Full article

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17 pages, 4796 KiB

Open AccessArticle

A Novel Artificial Hemoglobin Carrier Based on Heulandite-Calcium Mesoporous Aluminosilicate Particles

by Dino Jordanoski, Damjana Drobne, Neža Repar, Iztok Dogsa, Polona Mrak, Romana Cerc-Korošec, Andrijana Sever Škapin, Peter Nadrah and Natasa Poklar Ulrih

Int. J. Mol. Sci. 2022, 23(13), 7460; https://doi.org/10.3390/ijms23137460 - 5 Jul 2022

Cited by 1 | Viewed by 2457

Abstract

Tetraethyl-orthosilicate (TEOS)-based nanoparticles are most extensively used as a silica-based hemoglobin carrier system. However, TEOS-based nanoparticles induce adverse effects on the hemoglobin structure. Therefore, a heulandite-calcium-based carrier was investigated as a novel silica-based hemoglobin carrier system. The heulandite-calcium mesoporous aluminosilicate particles (MSPs) were [...] Read more.

Tetraethyl-orthosilicate (TEOS)-based nanoparticles are most extensively used as a silica-based hemoglobin carrier system. However, TEOS-based nanoparticles induce adverse effects on the hemoglobin structure. Therefore, a heulandite-calcium-based carrier was investigated as a novel silica-based hemoglobin carrier system. The heulandite-calcium mesoporous aluminosilicate particles (MSPs) were fabricated by a patented tribo-mechanical activation process, according to the manufacturer, and its structure was assessed by X-ray diffraction analysis. Upon hemoglobin encapsulation, alternation in the secondary and tertiary structure was observed. The hemoglobin-particle interactions do not cause heme degradation or decreased activity. Once encapsulated inside the particle pores, the hemoglobin shows increased thermal stability, and higher loading capacity per gram of particles (by a factor of >1.4) when compared to TEOS-based nanoparticles. Futhermore, we introduced a PEGlyted lipid bilayer which significantly decreases the premature hemoglobin release and increases the colloidal stability. The newly developed hemoglobin carrier shows no cytotoxicity to human umbilical vein endothelial cells (HUVEC). Full article

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13 pages, 5227 KiB

Open AccessArticle

Palladium Decorated N-Doped Carbon Foam as a Highly Active and Selective Catalyst for Nitrobenzene Hydrogenation

by Ádám Prekob, Ákos Szamosvölgyi, Gábor Muránszky, János Lakatos, Zoltán Kónya, Béla Fiser, Béla Viskolcz and László Vanyorek

Int. J. Mol. Sci. 2022, 23(12), 6423; https://doi.org/10.3390/ijms23126423 - 8 Jun 2022

Cited by 6 | Viewed by 2526

Abstract

Carbon foam was synthesized by the carbonization of 4-nitroaniline. The reaction is an alternative of the well-known “carbon snake” (or sugar snake) demonstration experiment, which leads to the formation of nitrogen-doped carbon foils due to its nitrogen content. The synthesized carbon foils were [...] Read more.

Carbon foam was synthesized by the carbonization of 4-nitroaniline. The reaction is an alternative of the well-known “carbon snake” (or sugar snake) demonstration experiment, which leads to the formation of nitrogen-doped carbon foils due to its nitrogen content. The synthesized carbon foils were grinded to achieve an efficient catalyst support. Palladium nanoparticles were deposited onto the surface of the support, which showed continuous distribution. The prepared Pd nanoparticle decorated carbon foils showed high catalytic activity in nitrobenzene hydrogenation. By applying the designed catalyst, total nitrobenzene conversion, a 99.1 n/n% aniline yield, and an exceptionally high selectivity (99.8 n/n%) were reached. Furthermore, the catalyst remained active during the reuse tests (four cycles) even without regeneration. Full article

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16 pages, 4289 KiB

Open AccessArticle

Towards Anion Recognition and Precipitation with Water-Soluble 1,2,4-Selenodiazolium Salts: Combined Structural and Theoretical Study

by Alexey A. Artemjev, Anton P. Novikov, Gleb M. Burkin, Alexander A. Sapronov, Alexey S. Kubasov, Valentine G. Nenajdenko, Victor N. Khrustalev, Alexander V. Borisov, Anatoly A. Kirichuk, Andreii S. Kritchenkov, Rosa M. Gomila, Antonio Frontera and Alexander G. Tskhovrebov

Int. J. Mol. Sci. 2022, 23(12), 6372; https://doi.org/10.3390/ijms23126372 - 7 Jun 2022

Cited by 20 | Viewed by 3192

Abstract

The synthesis and structural characterization of a series of supramolecular complexes of bicyclic cationic pyridine-fused 1,2,4-selenodiazoles with various anions is reported. The binding of trifluoroacetate, tetrachloroaurate, tetraphenylborate, perrhenate, and pertechnetate anions in the solid state is regarded. All the anions interact with selenodiazolium [...] Read more.

The synthesis and structural characterization of a series of supramolecular complexes of bicyclic cationic pyridine-fused 1,2,4-selenodiazoles with various anions is reported. The binding of trifluoroacetate, tetrachloroaurate, tetraphenylborate, perrhenate, and pertechnetate anions in the solid state is regarded. All the anions interact with selenodiazolium cations exclusively via a pair of “chelating” Se⋯O and H⋯O non-covalent interactions, which make them an attractive, novel, non-classical supramolecular recognition unit or a synthon. Trifluoroacetate salts were conveniently generated via novel oxidation reaction of 2,2′-dipyridyl diselenide with bis(trifluoroacetoxy)iodo)benzene in the presence of corresponding nitriles. Isolation and structural characterization of transient 2-pyridylselenyl trifluoroacetate was achieved. X-ray analysis has demonstrated that the latter forms dimers in the solid state featuring very short and strong Se⋯O and Se⋯N ChB contacts. 1,2,4-Selenodiazolium trifluoroacetates or halides show good solubility in water. In contrast, (AuCl₄)⁻, (ReO₄)⁻, or (TcO₄)⁻ derivatives immediately precipitate from aqueous solutions. Structural features of these supramolecular complexes in the solid state are discussed. The nature and energies of the non-covalent interactions in novel assembles were studied by the theoretical methods. To the best of our knowledge, this is the first study that regards perrhenate and pertechnetate as acceptors in ChB interactions. The results presented here will be useful for further developments in anion recognition and precipitation involving cationic 1,2,4-selenodiazoles. Full article

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13 pages, 2261 KiB

Open AccessReview

Design and Practical Considerations for Active Polymeric Films in Food Packaging

by Wing-Fu Lai and Wing-Tak Wong

Int. J. Mol. Sci. 2022, 23(11), 6295; https://doi.org/10.3390/ijms23116295 - 4 Jun 2022

Cited by 19 | Viewed by 4029

Abstract

Polymeric films for active food packaging have been playing an important role in food preservation due to favorable properties including high structural flexibility and high property tunability. Over the years, different polymeric active packaging films have been developed. Many of them have found [...] Read more.

Polymeric films for active food packaging have been playing an important role in food preservation due to favorable properties including high structural flexibility and high property tunability. Over the years, different polymeric active packaging films have been developed. Many of them have found real applications in food production. This article reviews, using a practical perspective, the principles of designing polymeric active packaging films. Different factors to be considered during materials selection and film generation are delineated. Practical considerations for the use of the generated polymeric films in active food packaging are also discussed. It is hoped that this article cannot only present a snapshot of latest advances in the design and optimization of polymeric active food packaging films, but insights into film development to achieve more effective active food packaging can be attained for future research. Full article

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10 pages, 2035 KiB

Open AccessArticle

Recombinant Human Thymosin β4 (rhTβ4) Modulates the Anti-Inflammatory Responses to Alleviate Benzalkonium Chloride (BAC)-Induced Dry Eye Disease

by Yanfang Zhai, Xiaoxiang Zheng, Yunyun Mao, Kai Li, Yanhong Liu, Yuemei Gao, Mengsu Zhao, Rui Yang, Rui Yu and Wei Chen

Int. J. Mol. Sci. 2022, 23(10), 5458; https://doi.org/10.3390/ijms23105458 - 13 May 2022

Cited by 11 | Viewed by 2697

Abstract

Dry eye disease (DED) is a multifactorial ocular disorder that interferes with daily living and reduces quality of life. However, there is no most ideal therapeutic treatment to address all the deleterious defects of DED. The purpose of this study was to investigate [...] Read more.

Dry eye disease (DED) is a multifactorial ocular disorder that interferes with daily living and reduces quality of life. However, there is no most ideal therapeutic treatment to address all the deleterious defects of DED. The purpose of this study was to investigate the ability of recombinant human thymosin β4 (rhTβ4) to promote healing in a benzalkonium chloride (BAC)-induced mice DED model and the anti-inflammatory effects involved in that process. Eye drops consisting of 0.05% and 0.1% rhTβ4 were used for treatment of DED. Tear volume and corneal staining scores were measured after 7 days. Periodic acid-Schiff staining for gobleT cells in conjunctiva, immunohistochemical staining for CD4⁺ T cells, TUNEL assay for apoptotic positive cells in cornea and conjunctiva, qRT-PCR and ELISA assays for multiple cytokines were performed. All clinical parameters showed improvement in both the 0.05% and 0.1% rhTβ4 groups. Specifically, topical application of rhTβ4 significantly increased conjunctival gobleT cells and reduced apoptotic cells in conjunctiva. Mechanically, the rhTβ4 groups showed significantly reduced inflammatory cytokine levels and CD4⁺ T cells in conjunctiva by blocking NF-κB (nuclear factor kappa B) activation, suggesting that 0.05–0.1% rhTβ4 eye drops may be used as a potential therapeutic treatment for DED. Full article

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11 pages, 5717 KiB

Open AccessArticle

Zwitterionic Modification of Polyethyleneimine for Efficient In Vitro siRNA Delivery

by Fengfan Liu, Huahui Su, Mengqian Li, Wanxuan Xie, Yunfeng Yan and Qi Shuai

Int. J. Mol. Sci. 2022, 23(9), 5014; https://doi.org/10.3390/ijms23095014 - 30 Apr 2022

Cited by 11 | Viewed by 3009

Abstract

Polyethylenimine (PEI) has been widely used in gene delivery. However, its high cytotoxicity and undesired non-specific protein adsorption hinder the overall delivery efficacy and the practical applications of PEI-based gene delivery systems. In this study, we prepared hydrophobically modified PEIs (H-PEIs) via the [...] Read more.

Polyethylenimine (PEI) has been widely used in gene delivery. However, its high cytotoxicity and undesired non-specific protein adsorption hinder the overall delivery efficacy and the practical applications of PEI-based gene delivery systems. In this study, we prepared hydrophobically modified PEIs (H-PEIs) via the reaction of octanal with 40% of primary amines in PEI_25k and PEI_10k, respectively. Two common zwitterionic molecules, 1,3-propanesultone and β-propiolactone, were then used for the modification of the resulting H-PEIs to construct polycationic gene carriers with zwitterionic properties (H-zPEIs). The siRNA delivery efficiency and cytotoxicity of these materials were evaluated in Hela-Luc and A549-Luc cell lines. Compared with their respective parental H-PEIs, different degrees of zwitterionic modification showed different effects in reducing cytotoxicity and delivery efficiency. All zwitterion-modified PEIs showed excellent siRNA binding capacity, reduced nonspecific protein adsorption, and enhanced stability upon nuclease degradation. It is concluded that zwitterionic molecular modification is an effective method to construct efficient vectors by preventing undesired interactions between polycationic carriers and biomacromolecules. It may offer insights into the modification of other cationic carriers of nucleic acid drugs. Full article

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10 pages, 2332 KiB

Open AccessArticle

Highly Tough, Stretchable and Self-Healing Polyampholyte Elastomers with Dual Adhesiveness

by Pengfei Yin, Yang Liu, Dan Huang and Chao Zhang

Int. J. Mol. Sci. 2022, 23(9), 4548; https://doi.org/10.3390/ijms23094548 - 20 Apr 2022

Cited by 3 | Viewed by 2373

Abstract

A new type of polyampholyte with unique viscoelastic properties can be easily synthesized by the copolymerization of butyl acrylate with dimethylaminoethyl methacrylate and acid acrylate in one pot. The elastic modulus of the as-prepared polyampholyte can be easily tuned by adjusting the ratio [...] Read more.

A new type of polyampholyte with unique viscoelastic properties can be easily synthesized by the copolymerization of butyl acrylate with dimethylaminoethyl methacrylate and acid acrylate in one pot. The elastic modulus of the as-prepared polyampholyte can be easily tuned by adjusting the ratio between the butyl acrylate and ionic monomers. The polyampholyte synthesized by a low proportion of ionic monomer showed low tensile strength and high stretchability, resulting in good conformal compliance with the biological tissues and potent energy dissipation. Due to the existence of high-intensity reversible ionic bonds in the polymer matrix, excellent self-recovery and self-healing properties were achieved on the as-prepared polyampholytes. By combining the high Coulombic interaction and interfacial energy dissipation, tough adhesiveness was obtained for the polyampholyte on various substrates. This new type of polyampholyte may have important applications in adhesives, packaging and tissue engineering. Full article

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14 pages, 4733 KiB

Open AccessReview

Cell-Based Chemical Safety Assessment and Therapeutic Discovery Using Array-Based Sensors

by Mingdi Jiang, Aritra Nath Chattopadhyay and Vincent M. Rotello

Int. J. Mol. Sci. 2022, 23(7), 3672; https://doi.org/10.3390/ijms23073672 - 27 Mar 2022

Cited by 7 | Viewed by 3617

Abstract

Synthetic chemicals are widely used in food, agriculture, and medicine, making chemical safety assessments necessary for environmental exposure. In addition, the rapid determination of chemical drug efficacy and safety is a key step in therapeutic discoveries. Cell-based screening methods are non-invasive as compared [...] Read more.

Synthetic chemicals are widely used in food, agriculture, and medicine, making chemical safety assessments necessary for environmental exposure. In addition, the rapid determination of chemical drug efficacy and safety is a key step in therapeutic discoveries. Cell-based screening methods are non-invasive as compared with animal studies. Cellular phenotypic changes can also provide more sensitive indicators of chemical effects than conventional cell viability. Array-based cell sensors can be engineered to maximize sensitivity to changes in cell phenotypes, lowering the threshold for detecting cellular responses under external stimuli. Overall, array-based sensing can provide a robust strategy for both cell-based chemical risk assessments and therapeutics discovery. Full article

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18 pages, 4846 KiB

Open AccessReview

Preparation and Modification Technology Analysis of Ionic Polymer-Metal Composites (IPMCs)

by Chendong He, Yunqing Gu, Junjun Zhang, Longbiao Ma, Muhan Yan, Jiegang Mou and Yun Ren

Int. J. Mol. Sci. 2022, 23(7), 3522; https://doi.org/10.3390/ijms23073522 - 24 Mar 2022

Cited by 32 | Viewed by 3837

Abstract

As a new type of flexible smart material, ionic polymer-metal composite (IPMC) has the advantages of being lightweight and having fast responses, good flexibility, and large deformation ranges. However, IPMC has the disadvantages of a small driving force and short lifespan. Based on [...] Read more.

As a new type of flexible smart material, ionic polymer-metal composite (IPMC) has the advantages of being lightweight and having fast responses, good flexibility, and large deformation ranges. However, IPMC has the disadvantages of a small driving force and short lifespan. Based on this, this paper firstly analyzes the driving mechanism of IPMC. Then, it focuses on the current preparation technology of IPMC from the aspects of electroless plating and mechanical plating. The advantages and disadvantages of various preparation methods are analyzed. Due to the special driving mechanism of IPMC, there is a problem of short non-aqueous working time. Therefore, the modification research of IPMC is reviewed from the aspects of the basement membrane, working medium, and electrode materials. Finally, the current challenges and future development prospects of IPMC are discussed. Full article

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37 pages, 15306 KiB

Open AccessReview

Improvements, Variations and Biomedical Applications of the Michaelis–Arbuzov Reaction

by Stavroula Kostoudi and Georgios Pampalakis

Int. J. Mol. Sci. 2022, 23(6), 3395; https://doi.org/10.3390/ijms23063395 - 21 Mar 2022

Cited by 13 | Viewed by 5977

Abstract

Compounds bearing the phosphorus–carbon (P–C) bond have important pharmacological, biochemical, and toxicological properties. Historically, the most notable reaction for the formation of the P–C bond is the Michaelis–Arbuzov reaction, first described in 1898. The classical Michaelis–Arbuzov reaction entails a reaction between an alkyl [...] Read more.

Compounds bearing the phosphorus–carbon (P–C) bond have important pharmacological, biochemical, and toxicological properties. Historically, the most notable reaction for the formation of the P–C bond is the Michaelis–Arbuzov reaction, first described in 1898. The classical Michaelis–Arbuzov reaction entails a reaction between an alkyl halide and a trialkyl phosphite to yield a dialkylalkylphosphonate. Nonetheless, deviations from the classical mechanisms and new modifications have appeared that allowed the expansion of the library of reactants and consequently the chemical space of the yielded products. These involve the use of Lewis acid catalysts, green methods, ultrasound, microwave, photochemically-assisted reactions, aryne-based reactions, etc. Here, a detailed presentation of the Michaelis–Arbuzov reaction and its developments and applications in the synthesis of biomedically important agents is provided. Certain examples of such applications include the development of alkylphosphonofluoridates as serine hydrolase inhibitors and activity-based probes, and the P–C containing antiviral and anticancer agents. Full article

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19 pages, 11502 KiB

Open AccessArticle

Tailoring ZE21B Alloy with Nature-Inspired Extracellular Matrix Secreted by Micro-Patterned Smooth Muscle Cells and Endothelial Cells to Promote Surface Biocompatibility

by Changsheng Liu, Lan Chen, Kun Zhang, Jingan Li and Shaokang Guan

Int. J. Mol. Sci. 2022, 23(6), 3180; https://doi.org/10.3390/ijms23063180 - 16 Mar 2022

Cited by 18 | Viewed by 2760

Abstract

Delayed surface endothelialization is a bottleneck that restricts the further application of cardiovascular stents. It has been reported that the nature-inspired extracellular matrix (ECM) secreted by the hyaluronic acid (HA) micro-patterned smooth muscle cells (SMC) and endothelial cells (EC) can significantly promote surface [...] Read more.

Delayed surface endothelialization is a bottleneck that restricts the further application of cardiovascular stents. It has been reported that the nature-inspired extracellular matrix (ECM) secreted by the hyaluronic acid (HA) micro-patterned smooth muscle cells (SMC) and endothelial cells (EC) can significantly promote surface endothelialization. However, this ECM coating obtained by decellularized method (dECM) is difficult to obtain directly on the surface of degradable magnesium (Mg) alloy. In this study, the method of obtaining bionic dECM by micro-patterning SMC/EC was further improved, and the nature-inspired ECM was prepared onto the Mg-Zn-Y-Nd (ZE21B) alloy surface by self-assembly. The results showed that the ECM coating not only improved surface endothelialization of ZE21B alloy, but also presented better blood compatibility, anti-hyperplasia, and anti-inflammation functions. The innovation and significance of the study is to overcome the disadvantage of traditional dECM coating and further expand the application of dECM coating to the surface of degradable materials and materials with different shapes. Full article

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20 pages, 11430 KiB

Open AccessArticle

Polymer–Metal Interfacial Friction Characteristics under Ultrasonic Plasticizing Conditions: A United-Atom Molecular Dynamics Study

by Wangqing Wu, Changsheng He, Yuanbao Qiang, Huajian Peng and Mingyong Zhou

Int. J. Mol. Sci. 2022, 23(5), 2829; https://doi.org/10.3390/ijms23052829 - 4 Mar 2022

Cited by 6 | Viewed by 2607

Abstract

Understanding the properties of polymer–metal interfacial friction is critical for accurate prototype design and process control in polymer-based advanced manufacturing. The transient polymer–metal interfacial friction characteristics are investigated using united-atom molecular dynamics in this study, which is under the boundary conditions of single [...] Read more.

Understanding the properties of polymer–metal interfacial friction is critical for accurate prototype design and process control in polymer-based advanced manufacturing. The transient polymer–metal interfacial friction characteristics are investigated using united-atom molecular dynamics in this study, which is under the boundary conditions of single sliding friction (SSF) and reciprocating sliding friction (RSF). It reflects the polymer–metal interaction under the conditions of initial compaction and ultrasonic vibration, so that the heat generation mechanism of ultrasonic plasticization microinjection molding (UPMIM) is explored. The contact mechanics, polymer segment rearrangement, and frictional energy transfer features of polymer–metal interface friction are investigated. The results reveal that, in both SSF and RSF modes, the sliding rate has a considerable impact on the dynamic response of the interfacial friction force, where the amplitude has a response time of about 0.6 ns to the friction. The high frequency movement of the polymer segment caused by dynamic interfacial friction may result in the formation of a new coupled interface. Frictional energy transfer is mainly characterized by dihedral and kinetic energy transitions in polymer chains. Our findings also show that the ultrasonic amplitude has a greater impact on polymer–metal interfacial friction heating than the frequency, as much as it does under ultrasonic plasticizing circumstances on the homogeneous polymer–polymer interface. Even if there are differences in thermophysical properties at the heterointerface, transient heating will still cause heat accumulation at the interface with a temperature difference of around 35 K. Full article

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15 pages, 6073 KiB

Open AccessArticle

Study on Spectral Selective Manipulation Characteristics of Surface Multilevel Micro–Nano Structures by FDTD Simulation

by Xiangjing Guo, Haiying Song, Bairui Du, Shengwang Tan and Shibing Liu

Int. J. Mol. Sci. 2022, 23(5), 2774; https://doi.org/10.3390/ijms23052774 - 2 Mar 2022

Cited by 4 | Viewed by 3264

Abstract

The optical filter based on the micro–nano structure on the material surface is an important optical device, which is widely used in many fields. The filter is fabricated on the substrate with different shapes and sizes of micro–nano array structure, and the wavelength [...] Read more.

The optical filter based on the micro–nano structure on the material surface is an important optical device, which is widely used in many fields. The filter is fabricated on the substrate with different shapes and sizes of micro–nano array structure, and the wavelength selectivity is realized by adjusting the processing parameters. In this paper, the finite-difference time-domain (FDTD) method is used to simulate the spectral properties of periodic array structures on the Au surface, and the spectral response characteristics of different surface structural parameters to the incident light are obtained. The simulation results show that the periodic pore array has a directional modulation function on the reflectivity and transmittance of the material surface. In the same circular aperture array structure, the wavelength selection ability is proportional to the interval distance of the array period, but the transmission peak linewidth decreases with the increase of the interval distance. The structural spectrum of the cylindrical array is closely related to the structural period. The period of the array structure increases in proportion, the center wavelengths of the reflection and transmission peak of the spectrum are red-shifted. When the height of the array structure increases proportionally, the positions of the center wavelengths of the reflection and transmission peak remain almost unchanged. When the period of the array structure increases, the center wavelength of the reflection and transmission peaks appear red-shifted, and the line width is also narrowed. For the periodic ring array structure, as the inner diameter increases, the reflection peak is significantly red-shifted, and the smaller the ring width, the faster the red-shift of the reflection peak with the wavelength. By controlling the ratio of inner diameter-to-outer diameter, the spectral characteristics of the structured surface can be effectively controlled. These simulation results provide a basis for the preparation of optical filters in the future and a new idea for the study of micro–nano characteristic structures on the surface of materials. Full article

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18 pages, 6111 KiB

Open AccessArticle

An Interleukin-4 and Interleukin-13 Induced Atopic Dermatitis Human Skin Equivalent Model by a Skin-On-A-Chip

by Kyunghee Kim, Hyeju Kim and Gun Yong Sung

Int. J. Mol. Sci. 2022, 23(4), 2116; https://doi.org/10.3390/ijms23042116 - 14 Feb 2022

Cited by 39 | Viewed by 9342

Abstract

Currently, the mechanism of progression of atopic dermatitis (AD) is not well understood because there is no physiologically appropriate disease model in terms of disease complexity and multifactoriality. Type 2 inflammation, mediated by interleukin (IL)-4 and IL-13, plays an important role in AD. [...] Read more.

Currently, the mechanism of progression of atopic dermatitis (AD) is not well understood because there is no physiologically appropriate disease model in terms of disease complexity and multifactoriality. Type 2 inflammation, mediated by interleukin (IL)-4 and IL-13, plays an important role in AD. In this study, full-thickness human skin equivalents consisting of human-derived cells were fabricated from pumpless microfluidic chips and stimulated with IL-4 and IL-13. The morphological properties, gene expression, cytokine secretion and protein expression of the stimulated human skin equivalent (HSE) epidermis were investigated. The results showed epidermal and spongy formations similar to those observed in lesions in AD, and decreased expression of barrier-related filaggrin, loricrin and involucrin genes and proteins induced by IL-4Rα signaling. In addition, we induced the expression of carbonic anhydrase II (CAII), a gene specifically expressed in the epidermis of patients with AD. Thus, AD human skin equivalents can be used to mimic the key pathological features of atopic dermatitis, overcoming the limitations of existing studies that rely solely on mouse models and have been unable to translate their effects to humans. Our results will be useful for future research on the development of therapeutic agents for atopic dermatitis. Full article

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29 pages, 8145 KiB

Open AccessArticle

The Influence of the Material Structure on the Mechanical Properties of Geopolymer Composites Reinforced with Short Fibers Obtained with Additive Technologies

by Kinga Korniejenko, Pavel Kejzlar and Petr Louda

Int. J. Mol. Sci. 2022, 23(4), 2023; https://doi.org/10.3390/ijms23042023 - 11 Feb 2022

Cited by 37 | Viewed by 3377

Abstract

Additive manufacturing technologies have a lot of potential advantages for construction application, including increasing geometrical construction flexibility, reducing labor costs, and improving efficiency and safety, and they are in line with the sustainable development policy. However, the full exploitation of additive manufacturing technology [...] Read more.

Additive manufacturing technologies have a lot of potential advantages for construction application, including increasing geometrical construction flexibility, reducing labor costs, and improving efficiency and safety, and they are in line with the sustainable development policy. However, the full exploitation of additive manufacturing technology for ceramic materials is currently limited. A promising solution in these ranges seems to be geopolymers reinforced by short fibers, but their application requires a better understanding of the behavior of this group of materials. The main objective of the article is to investigate the influence of the microstructure of the material on the mechanical properties of the two types of geopolymer composites (flax and carbon-reinforced) and to compare two methods of production of geopolymer composites (casting and 3D printing). As raw material for the matrix, fly ash from the Skawina coal power plant (located at: Skawina, Lesser Poland, Poland) was used. The provided research includes mechanical properties, microstructure investigations with the use of scanning electron microscope (SEM), confocal microscopy, and atomic force microscope (AFM), chemical and mineralogical (XRD-X-ray diffraction, and XRF-X-ray fluorescence), analysis of bonding in the materials (FT-IR), and nuclear magnetic resonance spectroscopy analysis (NMR). The best mechanical properties were reached for the sample made by simulating 3D printing process for the composite reinforced by flax fibers (48.7 MPa for the compressive strength and 9.4 MPa for flexural strength). The FT-IR, XRF and XRD results show similar composition of all investigated materials. NMR confirms the presence of SiO₄ and AlO₄ tetrahedrons in a three-dimensional structure that is crucial for geopolymer structure. The microscopy observations show a better coherence of the geopolymer made in additive technology to the reinforcement and equal fiber distribution for all investigated materials. The results show the samples made by the additive technology had comparable, or better, properties with those made by a traditional casting method. Full article

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11 pages, 1652 KiB

Open AccessArticle

Improved Production of 5-Hydroxymethylfurfural in Acidic Deep Eutectic Solvents Using Microwave-Assisted Reactions

by Eduarda S. Morais, Mara G. Freire, Carmen S. R. Freire and Armando J. D. Silvestre

Int. J. Mol. Sci. 2022, 23(4), 1959; https://doi.org/10.3390/ijms23041959 - 10 Feb 2022

Cited by 10 | Viewed by 3164

Abstract

Hydroxymethylfurfural (5-HMF) is a key platform chemical, essential for the production of other chemicals, as well as fuels. Despite its importance, the production methods applied so far still lack in sustainability. In this work, acidic deep eutectic solvents (DES), acting both as solvent [...] Read more.

Hydroxymethylfurfural (5-HMF) is a key platform chemical, essential for the production of other chemicals, as well as fuels. Despite its importance, the production methods applied so far still lack in sustainability. In this work, acidic deep eutectic solvents (DES), acting both as solvent and catalyst, were studied for the conversion of fructose into 5-HMF using microwave-assisted reactions. These solvents were screened and optimized by varying the hydrogen bond donor (HBD) and hydrogen bond acceptor (HBA). The bio-based solvent γ-valerolactone (GVL) was also applied as additive, leading to a boost in 5-HMF yield. Then, a response surface methodology was applied to further optimize operating conditions, such as reaction time, temperature and wt.% of added GVL. The highest 5-HMF yield attained, after optimization, was 82.4% at 130 °C, in 4 min of reaction time and with the addition of 10 wt.% of GVL. Moreover, a process for 5-HMF recovery and DES reuse was developed through the use of the bio-based solvent 2-methyltetrahydrofuran (2-Me-THF), allowing at least three cycles of 5-HMF production with minimal yield losses, while maintaining the purity of the isolated 5-HMF and the efficacy of the reaction media. Full article

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20 pages, 6351 KiB

Open AccessArticle

Reversible Redox Processes in Polymer of Unmetalated Salen-Type Ligand: Combined Electrochemical in Situ Studies and Direct Comparison with Corresponding Nickel Metallopolymer

by Julia Polozhentseva, Maria Novozhilova and Mikhail Karushev

Int. J. Mol. Sci. 2022, 23(3), 1795; https://doi.org/10.3390/ijms23031795 - 4 Feb 2022

Cited by 8 | Viewed by 2969

Abstract

Most non-metalized Salen-type ligands form passivation thin films on electrode surfaces upon electrochemical oxidation. In contrast, the H₂(3-MeOSalen) forms electroactive polymer films similarly to the corresponding nickel complex. There are no details of electrochemistry, doping mechanism and charge transfer pathways in [...] Read more.

Most non-metalized Salen-type ligands form passivation thin films on electrode surfaces upon electrochemical oxidation. In contrast, the H₂(3-MeOSalen) forms electroactive polymer films similarly to the corresponding nickel complex. There are no details of electrochemistry, doping mechanism and charge transfer pathways in the polymers of pristine Salen-type ligands. We studied a previously uncharacterized electrochemically active polymer of a Salen-type ligand H₂(3-MeOSalen) by a combination of cyclic voltammetry, in situ ultraviolet–visible (UV–VIS) spectroelectrochemistry, in situ electrochemical quartz crystal microbalance and Fourier Transform infrared spectroscopy (FTIR) spectroscopy. By directly comparing it with the polymer of a Salen-type nickel complex poly-Ni(3-MeOSalen) we elucidate the effect of the central metal atom on the structure and charge transport properties of the electrochemically doped polymer films. We have shown that the mechanism of charge transfer in the polymeric ligand poly-H₂(3-MeOSalen) are markedly different from the corresponding polymeric nickel complex. Due to deviation from planarity of N₂O₂ sphere for the ligand H₂(3-MeOSalen), the main pathway of electron transfer in the polymer film poly-H₂(3-MeOSalen) is between π-stacked structures (the π-electronic systems of phenyl rings are packed face-to-face) and C-C bonded phenyl rings. The main way of electron transfer in the polymer film poly-Ni(3-MeOSalen) is along the polymer chain, while redox processes are ligand-based. Full article

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18 pages, 40104 KiB

Open AccessArticle

Enhanced Tumor Imaging Using Glucosamine-Conjugated Polyacrylic Acid-Coated Ultrasmall Gadolinium Oxide Nanoparticles in Magnetic Resonance Imaging

by Shuwen Liu, Huan Yue, Son Long Ho, Soyeon Kim, Ji Ae Park, Tirusew Tegafaw, Mohammad Yaseen Ahmad, Seungho Kim, Abdullah Khamis Ali Al Saidi, Dejun Zhao, Ying Liu, Sung-Wook Nam, Kwon Seok Chae, Yongmin Chang and Gang Ho Lee

Int. J. Mol. Sci. 2022, 23(3), 1792; https://doi.org/10.3390/ijms23031792 - 4 Feb 2022

Cited by 4 | Viewed by 3369

Abstract

Owing to a higher demand for glucosamine (GlcN) in metabolic processes in tumor cells than in normal cells (i.e., GlcN effects), tumor imaging in magnetic resonance imaging (MRI) can be highly improved using GlcN-conjugated MRI contrast agents. Here, GlcN was conjugated with polyacrylic [...] Read more.

Owing to a higher demand for glucosamine (GlcN) in metabolic processes in tumor cells than in normal cells (i.e., GlcN effects), tumor imaging in magnetic resonance imaging (MRI) can be highly improved using GlcN-conjugated MRI contrast agents. Here, GlcN was conjugated with polyacrylic acid (PAA)-coated ultrasmall gadolinium oxide nanoparticles (UGONs) (d_avg = 1.76 nm). Higher positive (brighter or T₁) contrast enhancements at various organs including tumor site were observed in human brain glioma (U87MG) tumor-bearing mice after the intravenous injection of GlcN-PAA-UGONs into their tail veins, compared with those obtained with PAA-UGONs as control, which were rapidly excreted through the bladder. Importantly, the contrast enhancements of the GlcN-PAA-UGONs with respect to those of the PAA-UGONs were the highest in the tumor site owing to GlcN effects. These results demonstrated that GlcN-PAA-UGONs can serve as excellent T₁ MRI contrast agents in tumor imaging via GlcN effects. Full article

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14 pages, 1375 KiB

Open AccessArticle

Nanocarrier-Based Delivery of SN22 as a Tocopheryl Oxamate Prodrug Achieves Rapid Tumor Regression and Extends Survival in High-Risk Neuroblastoma Models

by Ivan S. Alferiev, David T. Guerrero, Danielle Soberman, Peng Guan, Ferro Nguyen, Venkatadri Kolla, Ilia Fishbein, Blake B. Pressly, Garrett M. Brodeur and Michael Chorny

Int. J. Mol. Sci. 2022, 23(3), 1752; https://doi.org/10.3390/ijms23031752 - 3 Feb 2022

Cited by 3 | Viewed by 2521

Abstract

Despite the use of intensive multimodality therapy, the majority of high-risk neuroblastoma (NB) patients do not survive. Without significant improvements in delivery strategies, anticancer agents used as a first-line treatment for high-risk tumors often fail to provide clinically meaningful results in the settings [...] Read more.

Despite the use of intensive multimodality therapy, the majority of high-risk neuroblastoma (NB) patients do not survive. Without significant improvements in delivery strategies, anticancer agents used as a first-line treatment for high-risk tumors often fail to provide clinically meaningful results in the settings of disseminated, recurrent, or refractory disease. By enhancing pharmacological selectivity, favorably shifting biodistribution, strengthening tumor cell killing potency, and overcoming drug resistance, nanocarrier-mediated delivery of topoisomerase I inhibitors of the camptothecin family has the potential to dramatically improve treatment efficacy and minimize side effects. In this study, a structurally enhanced camptothecin analog, SN22, reversibly coupled with a redox-silent tocol derivative (tocopheryl oxamate) to allow its optimally stable encapsulation and controlled release from PEGylated sub-100 nm nanoparticles (NP), exhibited strong NB cell growth inhibitory activity, translating into rapid regression and durably suppressed regrowth of orthotopic, MYCN-amplified NB tumors. The robust antitumor effects and markedly extended survival achieved in preclinical models recapitulating different phases of high-risk disease (at diagnosis vs. at relapse with an acquired loss of p53 function after intensive multiagent chemotherapy) demonstrate remarkable potential of SN22 delivered in the form of a hydrolytically cleavable superhydrophobic prodrug encapsulated in biodegradable nanocarriers as an experimental strategy for treating refractory solid tumors in high-risk cancer patients. Full article

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21 pages, 4721 KiB

Open AccessArticle

Silk Sericin Enrichment through Electrodeposition and Carbonous Materials for the Removal of Methylene Blue from Aqueous Solution

by Yansong Ji, Xiaoning Zhang, Zhenyu Chen, Yuting Xiao, Shiwei Li, Jie Gu, Hongmei Hu and Guotao Cheng

Int. J. Mol. Sci. 2022, 23(3), 1668; https://doi.org/10.3390/ijms23031668 - 31 Jan 2022

Cited by 10 | Viewed by 3429

Abstract

The recycling and reuse of biomass waste for the preparation of carbon-based adsorbents is a sustainable development strategy that has a positive environmental impact. It is well known that a large amount of silk sericin (SS) is dissolved in the wastewater from the [...] Read more.

The recycling and reuse of biomass waste for the preparation of carbon-based adsorbents is a sustainable development strategy that has a positive environmental impact. It is well known that a large amount of silk sericin (SS) is dissolved in the wastewater from the silk industry. Utilizing the SS instead of discharging it into the environment without further treatment would reduce environmental and ecological problems. However, effective enrichment of the SS from the aqueous solution is a challenge. Here, with the help of carboxymethyl chitosan (CMCS), which can form a gel structure under low voltage, an SS/CMCS hydrogel with SS as the major component was prepared via electrodeposition at a 3 V direct-current (DC) voltage for five minutes. Following a carbonization process, an SS-based adsorbent with good performance for the removal of methylene blue (MB) from an aqueous solution was prepared. Our results reveal that the SS/CMCS hydrogel maintains a porous architecture before and after carbonization. Such structure provides abundant adsorption sites facilitating the adsorption of MB molecules, with a maximum adsorptive capacity of 231.79 mg/g. In addition, it suggests that the adsorption is an exothermic process, has a good fit with the Langmuir model, and follows the intra-particle diffusion model. The presented work provides an economical and feasible path for the treatment of wastewater from dyeing and printing. Full article

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24 pages, 3513 KiB

Open AccessArticle

Quaternary Selenides EuLnCuSe₃: Synthesis, Structures, Properties and In Silico Studies

by Maxim V. Grigoriev, Leonid A. Solovyov, Anna V. Ruseikina, Aleksandr S. Aleksandrovsky, Vladimir A. Chernyshev, Dmitriy A. Velikanov, Alexander A. Garmonov, Maxim S. Molokeev, Aleksandr S. Oreshonkov, Nikolay P. Shestakov, Alexey V. Matigorov, Svetlana S. Volkova, Evgeniy A. Ostapchuk, Alexander V. Kertman, Thomas Schleid and Damir A. Safin

Int. J. Mol. Sci. 2022, 23(3), 1503; https://doi.org/10.3390/ijms23031503 - 28 Jan 2022

Cited by 19 | Viewed by 3189

Abstract

In this work, we report on the synthesis, in-depth crystal structure studies as well as optical and magnetic properties of newly synthesized heterometallic quaternary selenides of the Eu⁺²Ln⁺³Cu⁺¹Se₃ composition. Crystal structures of the obtained compounds were [...] Read more.

In this work, we report on the synthesis, in-depth crystal structure studies as well as optical and magnetic properties of newly synthesized heterometallic quaternary selenides of the Eu⁺²Ln⁺³Cu⁺¹Se₃ composition. Crystal structures of the obtained compounds were refined by the derivative difference minimization (DDM) method from the powder X-ray diffraction data. The structures are found to belong to orthorhombic space groups Pnma (structure type Ba₂MnS₃ for EuLaCuSe₃ and structure type Eu₂CuS₃ for EuLnCuSe₃, where Ln = Sm, Gd, Tb, Dy, Ho and Y) and Cmcm (structure type KZrCuS₃ for EuLnCuSe₃, where Ln = Tm, Yb and Lu). Space groups Pnma and Cmcm were delimited based on the tolerance factor t’, and vibrational spectroscopy additionally confirmed the formation of three structural types. With a decrease in the ionic radius of Ln³⁺ in the reported structures, the distortion of the (LnCuSe₃) layers decreases, and a gradual formation of the more symmetric structure occurs in the sequence Ba₂MnS₃ → Eu₂CuS₃ → KZrCuS₃. According to magnetic studies, compounds EuLnCuSe₃ (Ln = Tb, Dy, Ho and Tm) each exhibit ferrimagnetic properties with transition temperatures ranging from 4.7 to 6.3 K. A negative magnetization effect is observed for compound EuHoCuSe₃ at temperatures below 4.8 K. The magnetic properties of the discussed selenides and isostructural sulfides were compared. The direct optical band gaps for EuLnCuSe₃, subtracted from the corresponding diffuse reflectance spectra, were found to be 1.87–2.09 eV. Deviation between experimental and calculated band gaps is ascribed to lower d states of Eu²⁺ in the crystal field of EuLnCuSe₃, while anomalous narrowing of the band gap of EuYbCuSe₃ is explained by the low-lying charge-transfer state. Ab initio calculations of the crystal structures, elastic properties and phonon spectra of the reported compounds were performed. Full article

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21 pages, 4769 KiB

Open AccessArticle

Synthesis Mechanisms, Structural Models, and Photothermal Therapy Applications of Top-Down Carbon Dots from Carbon Powder, Graphite, Graphene, and Carbon Nanotubes

by Wenquan Shi, Qiurui Han, Jiajia Wu, Chunyu Ji, Yiqun Zhou, Shanghao Li, Lipeng Gao, Roger M. Leblanc and Zhili Peng

Int. J. Mol. Sci. 2022, 23(3), 1456; https://doi.org/10.3390/ijms23031456 - 27 Jan 2022

Cited by 67 | Viewed by 5112

Abstract

In this study, top-down syntheses of carbon dots (CDs) from four different carbon precursors, namely, carbon nano powders, graphite, graphene, and carbon nanotubes, were carried out. Systematic study demonstrated that the optical properties and surface functionalities of the CDs were quite similar and [...] Read more.

In this study, top-down syntheses of carbon dots (CDs) from four different carbon precursors, namely, carbon nano powders, graphite, graphene, and carbon nanotubes, were carried out. Systematic study demonstrated that the optical properties and surface functionalities of the CDs were quite similar and mainly influenced by the synthesis method, while the sizes, morphologies, chemical compositions, and core structures of the CDs were heavily influenced by the carbon precursors. On the basis of these studies, the formation processes and structural models of these four top-down CDs were proposed. The cell cytotoxicity and photothermal conversion efficiency of these CDs were also carefully evaluated, demonstrating their potential applications in photothermal therapy. Full article

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16 pages, 31687 KiB

Open AccessArticle

Temperature Dependence of Interfacial Bonding and Configuration Transition in Graphene/Hexagonal Boron Nitride Containing Grain Boundaries and Functional Groups

by Lei Fan and Wenjuan Yao

Int. J. Mol. Sci. 2022, 23(3), 1433; https://doi.org/10.3390/ijms23031433 - 27 Jan 2022

Cited by 9 | Viewed by 2210

Abstract

The quasi-three-dimensional effect induced by functional groups (FGo) and the in-plane stress and structural deformation induced by grain boundaries (GBs) may produce more novel physical effects. These physical effects are particularly significant in high-temperature environments and are different from the behavior in bulk [...] Read more.

The quasi-three-dimensional effect induced by functional groups (FGo) and the in-plane stress and structural deformation induced by grain boundaries (GBs) may produce more novel physical effects. These physical effects are particularly significant in high-temperature environments and are different from the behavior in bulk materials, so its physical mechanism is worth exploring. Considering the external field (strain and temperature field), the internal field (FGo and GBs) and the effect of distance between FGs and GBs on the bonding energy, configuration transition, and stress distribution of graphene/h-BN with FGo and GBs (GrO-BN-GBs) in the interface region were studied by molecular dynamics (MD). The results show that the regions linked by hydroxyl + epoxy groups gradually change from honeycomb to diamond-like structures as a result of a hybridization transition from sp² to sp³. The built-in distortion stress field generated by the coupling effect of temperature and tension loading induces the local geometric buckling of two-dimensional materials, according the von Mises stresses and deflection theory. In addition, the internal (FGo and GBs) and external field (strain and temperature field) have a negative chain reaction on the mechanical properties of GrO-BN-GBs, and the negative chain reaction increases gradually with the increase in the distance between FGo and GBs. These physical effects are particularly obvious in high-temperature environments, and the behavior of physical effects in two-dimensional materials is different from that in bulk materials, so its physical mechanism is worth exploring. Full article

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15 pages, 5779 KiB

Open AccessArticle

Combined Modification of Fiber Materials by Enzymes and Metal Nanoparticles for Chemical and Biological Protection

by Ilya Lyagin, Nikolay Stepanov, George Frolov and Elena Efremenko

Int. J. Mol. Sci. 2022, 23(3), 1359; https://doi.org/10.3390/ijms23031359 - 25 Jan 2022

Cited by 14 | Viewed by 4180

Abstract

To obtain fiber materials with pronounced chemical-biological protection, metal (Zn or Ta) nanoparticles were jointly applied with polyelectrolyte complexes of enzymes and polypeptides being their stabilizers. Computer modeling revealed the preferences between certain polyelectrolyte partners for N-acyl-homoserine lactone acylase and hexahistidine-tagged organophosphorus [...] Read more.

To obtain fiber materials with pronounced chemical-biological protection, metal (Zn or Ta) nanoparticles were jointly applied with polyelectrolyte complexes of enzymes and polypeptides being their stabilizers. Computer modeling revealed the preferences between certain polyelectrolyte partners for N-acyl-homoserine lactone acylase and hexahistidine-tagged organophosphorus hydrolase (His₆-OPH) possessing the quorum quenching (QQ) behavior with bacterial cells. The combinations of metal nanoparticles and enzymes appeared to function better as compared to the combinations of the same QQ-enzymes with antibiotics (polymyxins), making it possible to decrease the applied quantities by orders of magnitude while giving the same effect. The elimination of Gram-positive and Gram-negative bacterial cells from doubly modified fiber materials notably increased (up to 2.9-fold), whereas His₆-OPH retained its hydrolytic activity in reaction with organophosphorus compounds (up to 74% of initially applied activity). Materials with the certain enzyme and Zn nanoparticles were more efficient against Bacillus subtilis cells (up to 2.1-fold), and Ta nanoparticles acted preferentially against Escherichia coli (up to 1.5-fold). Some materials were proved to be more suitable for combined modification by metal nanoparticles and His₆-OPH complexes as antimicrobial protectants. Full article

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20 pages, 2398 KiB

Open AccessReview

Shape-Memory Polymers Hallmarks and Their Biomedical Applications in the Form of Nanofibers

by Silvia Pisani, Ida Genta, Tiziana Modena, Rossella Dorati, Marco Benazzo and Bice Conti

Int. J. Mol. Sci. 2022, 23(3), 1290; https://doi.org/10.3390/ijms23031290 - 24 Jan 2022

Cited by 35 | Viewed by 7781

Abstract

Shape-Memory Polymers (SMPs) are considered a kind of smart material able to modify size, shape, stiffness and strain in response to different external (heat, electric and magnetic field, water or light) stimuli including the physiologic ones such as pH, body temperature and ions [...] Read more.

Shape-Memory Polymers (SMPs) are considered a kind of smart material able to modify size, shape, stiffness and strain in response to different external (heat, electric and magnetic field, water or light) stimuli including the physiologic ones such as pH, body temperature and ions concentration. The ability of SMPs is to memorize their original shape before triggered exposure and after deformation, in the absence of the stimulus, and to recover their original shape without any help. SMPs nanofibers (SMPNs) have been increasingly investigated for biomedical applications due to nanofiber’s favorable properties such as high surface area per volume unit, high porosity, small diameter, low density, desirable fiber orientation and nanoarchitecture mimicking native Extra Cellular Matrix (ECM). This review focuses on the main properties of SMPs, their classification and shape-memory effects. Moreover, advantages in the use of SMPNs and different biomedical application fields are reported and discussed. Full article

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29 pages, 10428 KiB

Open AccessReview

Solid-State Preparation of Metal and Metal Oxides Nanostructures and Their Application in Environmental Remediation

by Carlos Diaz, Maria Luisa Valenzuela and Miguel Á. Laguna-Bercero

Int. J. Mol. Sci. 2022, 23(3), 1093; https://doi.org/10.3390/ijms23031093 - 20 Jan 2022

Cited by 15 | Viewed by 4511

Abstract

Nanomaterials have attracted much attention over the last decades due to their very different properties compared to those of bulk equivalents, such as a large surface-to-volume ratio, the size-dependent optical, physical, and magnetic properties. A number of solution fabrication methods have been developed [...] Read more.

Nanomaterials have attracted much attention over the last decades due to their very different properties compared to those of bulk equivalents, such as a large surface-to-volume ratio, the size-dependent optical, physical, and magnetic properties. A number of solution fabrication methods have been developed for the synthesis of metal and metal oxides nanoparticles, but few solid-state methods have been reported. The application of nanostructured materials to electronic solid-state devices or to high-temperature technology requires, however, adequate solid-state methods for obtaining nanostructured materials. In this review, we discuss some of the main current methods of obtaining nanomaterials in solid state, and also we summarize the obtaining of nanomaterials using a new general method in solid state. This new solid-state method to prepare metals and metallic oxides nanostructures start with the preparation of the macromolecular complexes chitosan·Xn and PS-co-4-PVP·MXn as precursors (X = anion accompanying the cationic metal, n = is the subscript, which indicates the number of anions in the formula of the metal salt and PS-co-4-PVP = poly(styrene-co-4-vinylpyridine)). Then, the solid-state pyrolysis under air and at 800 °C affords nanoparticles of M°, M_xO_y depending on the nature of the metal. Metallic nanoparticles are obtained for noble metals such as Au, while the respective metal oxide is obtained for transition, representative, and lanthanide metals. Size and morphology depend on the nature of the polymer as well as on the spacing of the metals within the polymeric chain. Noticeably in the case of TiO₂, anatase or rutile phases can be tuned by the nature of the Ti salts coordinated in the macromolecular polymer. A mechanism for the formation of nanoparticles is outlined on the basis of TG/DSC data. Some applications such as photocatalytic degradation of methylene by different metal oxides obtained by the presented solid-state method are also described. A brief review of the main solid-state methods to prepare nanoparticles is also outlined in the introduction. Some challenges to further development of these materials and methods are finally discussed. Full article

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13 pages, 1718 KiB

Open AccessArticle

Supported Lipid Bilayer Platform for Characterizing the Membrane-Disruptive Behaviors of Triton X-100 and Potential Detergent Replacements

by Negin Gooran, Bo Kyeong Yoon and Joshua A. Jackman

Int. J. Mol. Sci. 2022, 23(2), 869; https://doi.org/10.3390/ijms23020869 - 14 Jan 2022

Cited by 10 | Viewed by 5354

Abstract

Triton X-100 (TX-100) is a widely used detergent to prevent viral contamination of manufactured biologicals and biopharmaceuticals, and acts by disrupting membrane-enveloped virus particles. However, environmental concerns about ecotoxic byproducts are leading to TX-100 phase out and there is an outstanding need to [...] Read more.

Triton X-100 (TX-100) is a widely used detergent to prevent viral contamination of manufactured biologicals and biopharmaceuticals, and acts by disrupting membrane-enveloped virus particles. However, environmental concerns about ecotoxic byproducts are leading to TX-100 phase out and there is an outstanding need to identify functionally equivalent detergents that can potentially replace TX-100. To date, a few detergent candidates have been identified based on viral inactivation studies, while direct mechanistic comparison of TX-100 and potential replacements from a biophysical interaction perspective is warranted. Herein, we employed a supported lipid bilayer (SLB) platform to comparatively evaluate the membrane-disruptive properties of TX-100 and a potential replacement, Simulsol SL 11W (SL-11W), and identified key mechanistic differences in terms of how the two detergents interact with phospholipid membranes. Quartz crystal microbalance-dissipation (QCM-D) measurements revealed that TX-100 was more potent and induced rapid, irreversible, and complete membrane solubilization, whereas SL-11W caused more gradual, reversible membrane budding and did not induce extensive membrane solubilization. The results further demonstrated that TX-100 and SL-11W both exhibit concentration-dependent interaction behaviors and were only active at or above their respective critical micelle concentration (CMC) values. Collectively, our findings demonstrate that TX-100 and SL-11W have distinct membrane-disruptive effects in terms of potency, mechanism of action, and interaction kinetics, and the SLB platform approach can support the development of biophysical assays to efficiently test potential TX-100 replacements. Full article

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14 pages, 2552 KiB

Open AccessArticle

Effect of Thermocycling on the Bond Strength of Self-Adhesive Resin Cements Used for Luting CAD/CAM Ceramics to Human Dentin

by Andrzej Malysa, Joanna Wezgowiec, Wojciech Grzebieluch, Dariusz P. Danel and Mieszko Wieckiewicz

Int. J. Mol. Sci. 2022, 23(2), 745; https://doi.org/10.3390/ijms23020745 - 11 Jan 2022

Cited by 25 | Viewed by 3995

Abstract

The aim of the study was to evaluate the influence of thermocycling on the shear bond strength of self-adhesive, self-etching resin cements luted to human dentin and computer-aided design/computer-aided manufacturing (CAD/CAM) ceramics. Three modern self-adhesive dental cements (Maxcem Elite, RelyX U200, Panavia SA) [...] Read more.

The aim of the study was to evaluate the influence of thermocycling on the shear bond strength of self-adhesive, self-etching resin cements luted to human dentin and computer-aided design/computer-aided manufacturing (CAD/CAM) ceramics. Three modern self-adhesive dental cements (Maxcem Elite, RelyX U200, Panavia SA) were used to lute three CAD/CAM ceramics (IPS Empress CAD, IPS e.max CAD, IPS e.max ZirCAD) onto the dentin. One conventional cement (Panavia V5) served as a control. After preparation, the samples were subjected to thermocycling as a method of artificial aging of dental materials applied to simulate long-term use in oral conditions. Shear bond strength was evaluated according to PN-EN ISO 29022:2013-10 and failure modes were observed under a light microscope. Statistical analysis was performed. The study demonstrated that a combination of ceramics and cements directly impacts the bond strength. The highest bond strength was observed in Panavia V5, lower in Panavia SA and Maxcem Elite and the lowest–in RelyX U200. Adhesive failure between human dentin and cements was the most common failure mode. Moreover, thermocycling highly decreased bond strength of self-adhesive, self-etching cements. Full article

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2021

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12 pages, 5886 KiB

Open AccessArticle

Covalently Immobilized Regenerable Immunoaffinity Layer with Orientation-Controlled Antibodies Based on Z-Domain Autodisplay

by Jong-Min Park, Mi Yeon Kim, Joachim Jose and Min Park

Int. J. Mol. Sci. 2022, 23(1), 459; https://doi.org/10.3390/ijms23010459 - 31 Dec 2021

Cited by 18 | Viewed by 2107

Abstract

A regenerable immunoaffinity layer comprising covalently immobilized orientation-controlled antibodies was developed for use in a surface plasmon resonance (SPR) biosensor. For antibody orientation control, antibody-binding Z-domain-autodisplaying Escherichia coli (E. coli) cells and their outer membrane (OM) were utilized, and a disuccinimidyl [...] Read more.

A regenerable immunoaffinity layer comprising covalently immobilized orientation-controlled antibodies was developed for use in a surface plasmon resonance (SPR) biosensor. For antibody orientation control, antibody-binding Z-domain-autodisplaying Escherichia coli (E. coli) cells and their outer membrane (OM) were utilized, and a disuccinimidyl crosslinker was employed for covalent antibody binding. To fabricate the regenerable immunoaffinity layer, capture antibodies were bound to autodisplayed Z-domains, and then treated with the crosslinker for chemical fixation to the Z-domains. Various crosslinkers, namely disuccinimidyl glutarate (DSG), disuccinimidyl suberate (DSS) and poly (ethylene glycol)-ylated bis (sulfosuccinimidyl)suberate (BS(PEG)₅), were evaluated, and DSS at a concentration of 500 μM was confirmed to be optimal. The E. coli-cell-based regenerable HRP immunoassay was evaluated employing three sequential HRP treatment and regeneration steps. Then, the Oms of E. coli cells were isolated and layered on a microplate and regenerable OM-based HRP immunoassaying was evaluated. Five HRP immunoassays with four regeneration steps were found to be feasible. This regenerable, covalently immobilized, orientation-controlled OM-based immunoaffinity layer was applied to an SPR biosensor, which was capable of quantifying C-reactive protein (CRP). Five regeneration cycles were repeated using the demonstrated immunoaffinity layer with a signal difference of <10%. Full article

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16 pages, 4614 KiB

Open AccessArticle

Three Component Composite Scaffolds Based on PCL, Hydroxyapatite, and L-Lysine Obtained in TIPS-SL: Bioactive Material for Bone Tissue Engineering

by Aleksandra Korbut, Marcin Włodarczyk, Karolina Rudnicka, Aleksandra Szwed, Przemysław Płociński, Monika Biernat, Paulina Tymowicz-Grzyb, Martyna Michalska, Natalia Karska, Sylwia Rodziewicz-Motowidło and Konrad Szustakiewicz

Int. J. Mol. Sci. 2021, 22(24), 13589; https://doi.org/10.3390/ijms222413589 - 18 Dec 2021

Cited by 13 | Viewed by 3915

Abstract

In this research, we describe the properties of three-component composite foam scaffolds based on poly(ε-caprolactone) (PCL) as a matrix and hydroxyapatite whiskers (HAP) and L-Lysine as fillers (PCL/HAP/Lys with wt% ratio 50/48/2). The scaffolds were prepared using a thermally induced phase separation technique [...] Read more.

In this research, we describe the properties of three-component composite foam scaffolds based on poly(ε-caprolactone) (PCL) as a matrix and hydroxyapatite whiskers (HAP) and L-Lysine as fillers (PCL/HAP/Lys with wt% ratio 50/48/2). The scaffolds were prepared using a thermally induced phase separation technique supported by salt leaching (TIPS-SL). All materials were precisely characterized: porosity, density, water uptake, wettability, DSC, and TGA measurements and compression tests were carried out. The microstructure of the obtained scaffolds was analyzed via SEM. It was found that the PCL/HAP/Lys scaffold has a 45% higher Young’s modulus and better wettability compared to the PCL/HAP system. At the same time, the porosity of the system was ~90%. The osteoblast hFOB 1.19 cell response was also investigated in osteogenic conditions (39 °C) and the cytokine release profile of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α was determined. Modification of PCL scaffolds with HAP and L-Lysine significantly improved the proliferation of pre-osteoblasts cultured on such materials. Full article

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12 pages, 2747 KiB

Open AccessCommunication

Single Co₃O₄ Nanocubes Electrocatalyzing the Oxygen Evolution Reaction: Nano-Impact Insights into Intrinsic Activity and Support Effects

by Zhibin Liu, Manuel Corva, Hatem M. A. Amin, Niclas Blanc, Julia Linnemann and Kristina Tschulik

Int. J. Mol. Sci. 2021, 22(23), 13137; https://doi.org/10.3390/ijms222313137 - 4 Dec 2021

Cited by 23 | Viewed by 4096

Abstract

Single-entity electrochemistry allows for assessing electrocatalytic activities of individual material entities such as nanoparticles (NPs). Thus, it becomes possible to consider intrinsic electrochemical properties of nanocatalysts when researching how activity relates to physical and structural material properties. Conversely, conventional electrochemical techniques provide a [...] Read more.

Single-entity electrochemistry allows for assessing electrocatalytic activities of individual material entities such as nanoparticles (NPs). Thus, it becomes possible to consider intrinsic electrochemical properties of nanocatalysts when researching how activity relates to physical and structural material properties. Conversely, conventional electrochemical techniques provide a normalized sum current referring to a huge ensemble of NPs constituting, along with additives (e.g., binders), a complete catalyst-coated electrode. Accordingly, recording electrocatalytic responses of single NPs avoids interferences of ensemble effects and reduces the complexity of electrocatalytic processes, thus enabling detailed description and modelling. Herein, we present insights into the oxygen evolution catalysis at individual cubic Co₃O₄ NPs impacting microelectrodes of different support materials. Simulating diffusion at supported nanocubes, measured step current signals can be analyzed, providing edge lengths, corresponding size distributions, and interference-free turnover frequencies. The provided nano-impact investigation of (electro-)catalyst-support effects contradicts assumptions on a low number of highly active sites. Full article

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38 pages, 2406 KiB

Open AccessReview

Possible Treatment of Myocardial Infarct Based on Tissue Engineering Using a Cellularized Solid Collagen Scaffold Functionalized with Arg-Glyc-Asp (RGD) Peptide

by Olivier Schussler, Pierre E. Falcoz, Juan C. Chachques, Marco Alifano and Yves Lecarpentier

Int. J. Mol. Sci. 2021, 22(22), 12563; https://doi.org/10.3390/ijms222212563 - 22 Nov 2021

Cited by 11 | Viewed by 3956

Abstract

Currently, the clinical impact of cell therapy after a myocardial infarction (MI) is limited by low cell engraftment due to low cell retention, cell death in inflammatory and poor angiogenic infarcted areas, secondary migration. Cells interact with their microenvironment through integrin mechanoreceptors that [...] Read more.

Currently, the clinical impact of cell therapy after a myocardial infarction (MI) is limited by low cell engraftment due to low cell retention, cell death in inflammatory and poor angiogenic infarcted areas, secondary migration. Cells interact with their microenvironment through integrin mechanoreceptors that control their survival/apoptosis/differentiation/migration and proliferation. The association of cells with a three-dimensional material may be a way to improve interactions with their integrins, and thus outcomes, especially if preparations are epicardially applied. In this review, we will focus on the rationale for using collagen as a polymer backbone for tissue engineering of a contractile tissue. Contractilities are reported for natural but not synthetic polymers and for naturals only for: collagen/gelatin/decellularized-tissue/fibrin/Matrigel™ and for different material states: hydrogels/gels/solids. To achieve a thick/long-term contractile tissue and for cell transfer, solid porous compliant scaffolds are superior to hydrogels or gels. Classical methods to produce solid scaffolds: electrospinning/freeze-drying/3D-printing/solvent-casting and methods to reinforce and/or maintain scaffold properties by reticulations are reported. We also highlight the possibility of improving integrin interaction between cells and their associated collagen by its functionalizing with the RGD-peptide. Using a contractile patch that can be applied epicardially may be a way of improving ventricular remodeling and limiting secondary cell migration. Full article

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16 pages, 9116 KiB

Open AccessArticle

Green Synthesis of Silver Nanoparticles Using Olea europaea Leaf Extract for Their Enhanced Antibacterial, Antioxidant, Cytotoxic and Biocompatibility Applications

by Hanen Sellami, Shakeel Ahmad Khan, Ishaq Ahmad, Abdullah A. Alarfaj, Abdurahman H. Hirad and Ahmed E. Al-Sabri

Int. J. Mol. Sci. 2021, 22(22), 12562; https://doi.org/10.3390/ijms222212562 - 22 Nov 2021

Cited by 37 | Viewed by 4233

Abstract

Herein, we report the green synthesis of silver nanoparticles (OE-Ag NPs) by ecofriendly green processes using biological molecules of Olea europaea leaf extract. Green synthesized OE-Ag NPs were successfully characterized using different spectroscopic techniques. Antibacterial activity of OE-Ag NPs was assessed against four [...] Read more.

Herein, we report the green synthesis of silver nanoparticles (OE-Ag NPs) by ecofriendly green processes using biological molecules of Olea europaea leaf extract. Green synthesized OE-Ag NPs were successfully characterized using different spectroscopic techniques. Antibacterial activity of OE-Ag NPs was assessed against four different bacteriological strains using the dilution serial method. The cytotoxic potential was determined against MCF-7 carcinoma cells using MTT assay in terms of cell viability percentage. Antioxidant properties were evaluated in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. Biocompatibility was further examined by incubating the synthesized NPs with hMSC cells for 24 h. The results were demonstrated that synthesized OE-Ag NPs presented excellent log₁₀ reduction in the growth of all the tested bacterial strains, which as statistically equivalent (p > 0.05) to the standard antibiotic drug. Moreover, they also demonstrated excellent cytotoxic efficacy against the MCF-7 carcinoma cells compared to plant lead extract and Com-Ag NPs. Green synthesized OE-Ag NPs appeared more biocompatible to hMSC and 293T cells compared to Com-Ag NPs. Excellent biological results of the OE-Ag NPs might be attributed to the synergetic effect of NPs’ properties and the adsorbed secondary metabolites of plant leaf extract. Hence, this study suggests that synthesized OE-Ag NPs can be a potential contender for their various biological and nutraceutical applications. Moreover, this study will open a new avenue to produce biocompatible nanoparticles with additional biological functionalities from the plants. Full article

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22 pages, 956 KiB

Open AccessReview

Nanoparticles for Targeted Brain Drug Delivery: What Do We Know?

by Rúben G. R. Pinheiro, Ana Joyce Coutinho, Marina Pinheiro and Ana Rute Neves

Int. J. Mol. Sci. 2021, 22(21), 11654; https://doi.org/10.3390/ijms222111654 - 28 Oct 2021

Cited by 114 | Viewed by 11083

Abstract

The blood–brain barrier (BBB) is a barrier that separates the blood from the brain tissue and possesses unique characteristics that make the delivery of drugs to the brain a great challenge. To achieve this purpose, it is necessary to design strategies to allow [...] Read more.

The blood–brain barrier (BBB) is a barrier that separates the blood from the brain tissue and possesses unique characteristics that make the delivery of drugs to the brain a great challenge. To achieve this purpose, it is necessary to design strategies to allow BBB passage, in order to reach the brain and target the desired anatomic region. The use of nanomedicine has great potential to overcome this problem, since one can modify nanoparticles with strategic molecules that can interact with the BBB and induce uptake through the brain endothelial cells and consequently reach the brain tissue. This review addresses the potential of nanomedicines to treat neurological diseases by using nanoparticles specially developed to cross the BBB. Full article

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20 pages, 4506 KiB

Open AccessArticle

Tension Stimulation of Tenocytes in Aligned Hyaluronic Acid/Platelet-Rich Plasma-Polycaprolactone Core-Sheath Nanofiber Membrane Scaffold for Tendon Tissue Engineering

by Chih-Hao Chen, Dai-Ling Li, Andy Deng-Chi Chuang, Banendu Sunder Dash and Jyh-Ping Chen

Int. J. Mol. Sci. 2021, 22(20), 11215; https://doi.org/10.3390/ijms222011215 - 18 Oct 2021

Cited by 27 | Viewed by 3849

Abstract

To recreate the in vivo niche for tendon tissue engineering in vitro, the characteristics of tendon tissue underlines the use of biochemical and biophysical cues during tenocyte culture. Herein, we prepare core-sheath nanofibers with polycaprolactone (PCL) sheath for mechanical support and hyaluronic acid [...] Read more.

To recreate the in vivo niche for tendon tissue engineering in vitro, the characteristics of tendon tissue underlines the use of biochemical and biophysical cues during tenocyte culture. Herein, we prepare core-sheath nanofibers with polycaprolactone (PCL) sheath for mechanical support and hyaluronic acid (HA)/platelet-rich plasma (PRP) core for growth factor delivery. Three types of core-sheath nanofiber membrane scaffolds (CSNMS), consisting of random HA-PCL nanofibers (Random), random HA/PRP-PCL nanofibers (Random+) or aligned HA/PRP-PCL (Align⁺) nanofibers, were used to study response of rabbit tenocytes to biochemical (PRP) and biophysical (fiber alignment) stimulation. The core-sheath structures as well as other pertinent properties of CSNMS have been characterized, with Align⁺ showing the best mechanical properties. The unidirectional growth of tenocytes, as induced by aligned fiber topography, was confirmed from cell morphology and cytoskeleton expression. The combined effects of PRP and fiber alignment in Align⁺ CSNMS lead to enhanced cell proliferation rates, as well as upregulated gene expression and marker protein synthesis. Another biophysical cue on tenocytes was introduced by dynamic culture of tenocyte-seeded Align⁺ in a bioreactor with cyclic tension stimulation. Augmented by this biophysical beacon from mechanical loading, dynamic cell culture could shorten the time for tendon maturation in vitro, with improved cell proliferation rates and tenogenic phenotype maintenance, compared to static culture. Therefore, we successfully demonstrate how combined use of biochemical/topographical cues as well as mechanical stimulation could ameliorate cellular response of tenocytes in CSNMS, which can provide a functional in vitro environmental niche for tendon tissue engineering. Full article

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19 pages, 1947 KiB

Open AccessArticle

Design of Gelatin-Capped Plasmonic-Diatomite Nanoparticles with Enhanced Galunisertib Loading Capacity for Drug Delivery Applications

by Chiara Tramontano, Bruno Miranda, Giovanna Chianese, Luca De Stefano, Carlo Forestiere, Marinella Pirozzi and Ilaria Rea

Int. J. Mol. Sci. 2021, 22(19), 10755; https://doi.org/10.3390/ijms221910755 - 5 Oct 2021

Cited by 19 | Viewed by 4887

Abstract

Inorganic diatomite nanoparticles (DNPs) have gained increasing interest as drug delivery systems due to their porous structure, long half-life, thermal and chemical stability. Gold nanoparticles (AuNPs) provide DNPs with intriguing optical features that can be engineered and optimized for sensing and drug delivery [...] Read more.

Inorganic diatomite nanoparticles (DNPs) have gained increasing interest as drug delivery systems due to their porous structure, long half-life, thermal and chemical stability. Gold nanoparticles (AuNPs) provide DNPs with intriguing optical features that can be engineered and optimized for sensing and drug delivery applications. In this work, we combine DNPs with gelatin stabilized AuNPs for the development of an optical platform for Galunisertib delivery. To improve the DNP loading capacity, the hybrid platform is capped with gelatin shells of increasing thicknesses. Here, for the first time, full optical modeling of the hybrid system is proposed to monitor both the gelatin generation, degradation, and consequent Galunisertib release by simple spectroscopic measurements. Indeed, the shell thickness is optically estimated as a function of the polymer concentration by exploiting the localized surface plasmon resonance shifts of AuNPs. We simultaneously prove the enhancement of the drug loading capacity of DNPs and that the theoretical modeling represents an efficient predictive tool to design polymer-coated nanocarriers. Full article

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12 pages, 3335 KiB

Open AccessCommunication

Engineering Efficient Self-Assembled Plasmonic Nanostructures by Configuring Metallic Nanoparticle’s Morphology

by Vasanthan Devaraj, Jong-Min Lee, Ye-Ji Kim, Hyuk Jeong and Jin-Woo Oh

Int. J. Mol. Sci. 2021, 22(19), 10595; https://doi.org/10.3390/ijms221910595 - 30 Sep 2021

Cited by 12 | Viewed by 4410

Abstract

We reveal the significance of plasmonic nanoparticle’s (NP) shape and its surface morphology en route to an efficient self-assembled plasmonic nanoparticle cluster. A simplified model is simulated in the form of free-space dimer and trimer nanostructures (NPs in the shape of a sphere, [...] Read more.

We reveal the significance of plasmonic nanoparticle’s (NP) shape and its surface morphology en route to an efficient self-assembled plasmonic nanoparticle cluster. A simplified model is simulated in the form of free-space dimer and trimer nanostructures (NPs in the shape of a sphere, cube, and disk). A ~200% to ~125% rise in near-field strength (gap mode enhancement) is observed for spherical NPs in comparison with cubical NPs (from 2 nm to 8 nm gap sizes). Full-width three-quarter maximum reveals better broad-spectral optical performance in a range of ~100 nm (dimer) and ~170 nm (trimer) from spherical NPs as compared to a cube (~60 nm for dimer and trimer). These excellent properties for sphere-based nanostructures are merited from its dipole mode characteristics. Full article

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28 pages, 5207 KiB

Open AccessReview

State of the Art in the Antibacterial and Antiviral Applications of Carbon-Based Polymeric Nanocomposites

by Ana M. Díez-Pascual

Int. J. Mol. Sci. 2021, 22(19), 10511; https://doi.org/10.3390/ijms221910511 - 29 Sep 2021

Cited by 45 | Viewed by 4319

Abstract

The development of novel approaches to prevent bacterial infection is essential for enhancing everyday life. Carbon nanomaterials display exceptional optical, thermal, and mechanical properties combined with antibacterial ones, which make them suitable for diverse fields, including biomedical and food applications. Nonetheless, their practical [...] Read more.

The development of novel approaches to prevent bacterial infection is essential for enhancing everyday life. Carbon nanomaterials display exceptional optical, thermal, and mechanical properties combined with antibacterial ones, which make them suitable for diverse fields, including biomedical and food applications. Nonetheless, their practical applications as antimicrobial agents have not been fully explored yet, owing to their relatively poor dispersibility, expensiveness, and scalability changes. To solve these issues, they can be integrated within polymeric matrices, which also exhibit antimicrobial activity in some cases. This review describes the state of the art in the antibacterial applications of polymeric nanocomposites reinforced with 0D fullerenes, 1D carbon nanotubes (CNTs), and 2D graphene (G) and its derivatives such as graphene oxide (GO) and reduced graphene oxide (rGO). Given that a large number of such nanocomposites are available, only the most illustrative examples are described, and their mechanisms of antimicrobial activity are discussed. Finally, some applications of these antimicrobial polymeric nanocomposites are reviewed. Full article

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22 pages, 8458 KiB

Open AccessArticle

Air-Spun Silk-Based Micro-/Nanofibers and Thin Films for Drug Delivery

by Christopher R. Gough and Xiao Hu

Int. J. Mol. Sci. 2021, 22(17), 9588; https://doi.org/10.3390/ijms22179588 - 3 Sep 2021

Cited by 6 | Viewed by 4417

Abstract

Micro-/nanofibers have shown high promise as drug delivery vehicles due to their high porosity and surface-area-to-volume ratio. The current study utilizes air-spraying, a novel fiber fabrication technique, to create silk micro-/nanofibers without the need for a high voltage power source. Air-spraying was used [...] Read more.

Micro-/nanofibers have shown high promise as drug delivery vehicles due to their high porosity and surface-area-to-volume ratio. The current study utilizes air-spraying, a novel fiber fabrication technique, to create silk micro-/nanofibers without the need for a high voltage power source. Air-spraying was used to create silk fibrous mats embedded with several model drugs with high efficiency. In order to compare the effect of biomaterial geometry on the release of the model drugs, silk films were also created and characterized. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and a drug release study were performed on both fiber and film samples to study how the model drugs interact with the protein structure. FTIR analysis showed that while drugs could interact with the protein structure of porous silk fibers, they could not interact with the flat geometry of silk films. As a result, fibers could protect select model drugs from thermal degradation and slow their release from the fiber network with more control than the silk films. A trend was also revealed where hydrophobic drugs were better protected and had a slower release than hydrophilic drugs. The results suggest that the physical and chemical properties of drugs and protein-based biomaterials are important for creating drug delivery vehicles with tailored release profiles and that fibers provide better tunability than films do. Full article

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26 pages, 5484 KiB

Open AccessArticle

Increasing Angiogenesis Factors in Hypoxic Diabetic Wound Conditions by siRNA Delivery: Additive Effect of LbL-Gold Nanocarriers and Desloratadine-Induced Lysosomal Escape

by Elnaz Shaabani, Maryam Sharifiaghdam, Joris Lammens, Herlinde De Keersmaecker, Chris Vervaet, Thomas De Beer, Elahe Motevaseli, Mohammad Hossein Ghahremani, Parvin Mansouri, Stefaan De Smedt, Koen Raemdonck, Reza Faridi-Majidi, Kevin Braeckmans and Juan C. Fraire

Int. J. Mol. Sci. 2021, 22(17), 9216; https://doi.org/10.3390/ijms22179216 - 26 Aug 2021

Cited by 22 | Viewed by 4336

Abstract

Impaired wound healing in people with diabetes has multifactorial causes, with insufficient neovascularization being one of the most important. Hypoxia-inducible factor-1 (HIF-1) plays a central role in the hypoxia-induced response by activating angiogenesis factors. As its activity is under precise regulatory control of [...] Read more.

Impaired wound healing in people with diabetes has multifactorial causes, with insufficient neovascularization being one of the most important. Hypoxia-inducible factor-1 (HIF-1) plays a central role in the hypoxia-induced response by activating angiogenesis factors. As its activity is under precise regulatory control of prolyl-hydroxylase domain 2 (PHD-2), downregulation of PHD-2 by small interfering RNA (siRNA) could stabilize HIF-1α and, therefore, upregulate the expression of pro-angiogenic factors as well. Intracellular delivery of siRNA can be achieved with nanocarriers that must fulfill several requirements, including high stability, low toxicity, and high transfection efficiency. Here, we designed and compared the performance of layer-by-layer self-assembled siRNA-loaded gold nanoparticles with two different outer layers—Chitosan (AuNP@CS) and Poly L-arginine (AuNP@PLA). Although both formulations have exactly the same core, we find that a PLA outer layer improves the endosomal escape of siRNA, and therefore, transfection efficiency, after endocytic uptake in NIH-3T3 cells. Furthermore, we found that endosomal escape of AuNP@PLA could be improved further when cells were additionally treated with desloratadine, thus outperforming commercial reagents such as Lipofectamine^® and jetPRIME^®. AuNP@PLA in combination with desloratadine was proven to induce PHD-2 silencing in fibroblasts, allowing upregulation of pro-angiogenic pathways. This finding in an in vitro context constitutes a first step towards improving diabetic wound healing with siRNA therapy. Full article

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16 pages, 4072 KiB

Open AccessArticle

Injectable Thixotropic β–Cyclodextrin–Functionalized Hydrogels Based on Guanosine Quartet Assembly

by Monica-Cornelia Sardaru, Irina Rosca, Simona Morariu, Elena-Laura Ursu, Razvan Ghiarasim and Alexandru Rotaru

Int. J. Mol. Sci. 2021, 22(17), 9179; https://doi.org/10.3390/ijms22179179 - 25 Aug 2021

Cited by 2 | Viewed by 3232

Abstract

Facile method for the preparation of β–cyclodextrin–functionalized hydrogels based on guanosine quartet assembly was described. A series of seven hydrogels were prepared by linking β–cyclodextrin molecules with guanosine moieties in different ratios through benzene–1,4–diboronic acid linker in the presence of potassium hydroxide. The [...] Read more.

Facile method for the preparation of β–cyclodextrin–functionalized hydrogels based on guanosine quartet assembly was described. A series of seven hydrogels were prepared by linking β–cyclodextrin molecules with guanosine moieties in different ratios through benzene–1,4–diboronic acid linker in the presence of potassium hydroxide. The potassium ions acted as a reticulation agent by forming guanosine quartets, leading to the formation of self–sustained transparent hydrogels. The ratios of the β–cyclodextrin and guanosine components have a significant effect on the internal structuration of the components and, correspondingly, on the mechanical properties of the final gels, offering a tunablity of the system by varying the components ratio. The insights into the hydrogels’ structuration were achieved by circular dichroism, scanning electron microscopy, atomic force microscopy, and X–ray diffraction. Rheological measurements revealed self–healing and thixotropic properties of all the investigated samples, which, in combination with available cyclodextrin cavities for active components loading, make them remarkable candidates for specific applications in biomedical and pharmaceutical fields. Moreover, all the prepared samples displayed selective antimicrobial properties against S. aureus in planktonic and biofilm phase, the activity also depending on the guanosine and cyclodextrin ratio within the hydrogel structure. Full article

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10 pages, 3283 KiB

Open AccessArticle

Super-Toughened Fumed-Silica-Reinforced Thiol-Epoxy Composites Containing Epoxide-Terminated Polydimethylsiloxanes

by Goseong Bok, Gayoung Lim, Mingi Kwak and Youngmin Kim

Int. J. Mol. Sci. 2021, 22(15), 8097; https://doi.org/10.3390/ijms22158097 - 28 Jul 2021

Cited by 5 | Viewed by 2640 | Correction

Abstract

In response to the demand for high-performance materials, epoxy thermosetting and its composites are widely used in various industries. However, their poor toughness, resulting from the high crosslinking density of the epoxy network, must be improved to expand their application to the manufacturing [...] Read more.

In response to the demand for high-performance materials, epoxy thermosetting and its composites are widely used in various industries. However, their poor toughness, resulting from the high crosslinking density of the epoxy network, must be improved to expand their application to the manufacturing of flexible products. In this study, ductile epoxy thermosetting was produced using thiol compounds with functionalities of 2 and 3 as curing agents. The mechanical properties of the epoxy were further enhanced by incorporating fumed silica into it. To increase the filler dispersion, epoxide-terminated polydimethylsiloxane was synthesized and used as a composite component. Thanks to the polysiloxane–silica interaction, the nanosilica was uniformly dispersed in the epoxy composites, and their mechanical properties improved with increasing fumed silica content up to 5 phr (parts per hundred parts of epoxy resin). The toughness and impact strength of the composite containing 5 phr nanosilica were 5.17 (±0.13) MJ/m³ and 69.8 (±1.3) KJ/m², respectively. Full article

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22 pages, 8950 KiB

Open AccessArticle

Layer by Layer Assembled Chitosan-Coated Gold Nanoparticles for Enhanced siRNA Delivery and Silencing

by Elnaz Shaabani, Maryam Sharifiaghdam, Herlinde De Keersmaecker, Riet De Rycke, Stefaan De Smedt, Reza Faridi-Majidi, Kevin Braeckmans and Juan C. Fraire

Int. J. Mol. Sci. 2021, 22(2), 831; https://doi.org/10.3390/ijms22020831 - 15 Jan 2021

Cited by 48 | Viewed by 5272

Abstract

Delivery of small interfering RNA (siRNA) provides one of the most powerful strategies for downregulation of therapeutic targets. Despite the widely explored capabilities of this strategy, intracellular delivery is hindered by a lack of carriers that have high stability, low toxicity and high [...] Read more.

Delivery of small interfering RNA (siRNA) provides one of the most powerful strategies for downregulation of therapeutic targets. Despite the widely explored capabilities of this strategy, intracellular delivery is hindered by a lack of carriers that have high stability, low toxicity and high transfection efficiency. Here we propose a layer by layer (LBL) self-assembly method to fabricate chitosan-coated gold nanoparticles (CS-AuNPs) as a more stable and efficient siRNA delivery system. Direct reduction of HAuCl₄ in the presence of chitosan led to the formation of positively charged CS-AuNPs, which were subsequently modified with a layer of siRNA cargo molecules and a final chitosan layer to protect the siRNA and to have a net positive charge for good interaction with cells. Cytotoxicity, uptake, and downregulation of enhanced Green Fluorescent Protein (eGFP) in H1299-eGFP lung epithelial cells indicated that LBL-CS-AuNPs provided excellent protection of siRNA against enzymatic degradation, ensured good uptake in cells by endocytosis, facilitated endosomal escape of siRNA, and improved the overall silencing effect in comparison with commercial transfection reagents Lipofectamine and jetPEI^®. Therefore, this work shows that LBL assembled CS-AuNPs are promising nanocarriers for enhanced intracellular siRNA delivery and silencing. Full article

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2020

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16 pages, 270 KiB

Open AccessReview

The Body’s Cellular and Molecular Response to Protein-Coated Medical Device Implants: A Review Focused on Fibronectin and BMP Proteins

by Yi-Fan Chen, Clyde Goodheart and Diego Rua

Int. J. Mol. Sci. 2020, 21(22), 8853; https://doi.org/10.3390/ijms21228853 - 23 Nov 2020

Cited by 8 | Viewed by 3764

Abstract

Recent years have seen a marked rise in implantation into the body of a great variety of devices: hip, knee, and shoulder replacements, pacemakers, meshes, glucose sensors, and many others. Cochlear and retinal implants are being developed to restore hearing and sight. After [...] Read more.

Recent years have seen a marked rise in implantation into the body of a great variety of devices: hip, knee, and shoulder replacements, pacemakers, meshes, glucose sensors, and many others. Cochlear and retinal implants are being developed to restore hearing and sight. After surgery to implant a device, adjacent cells interact with the implant and release molecular signals that result in attraction, infiltration of the tissue, and attachment to the implant of various cell types including monocytes, macrophages, and platelets. These cells release additional signaling molecules (chemokines and cytokines) that recruit tissue repair cells to the device site. Some implants fail and require additional revision surgery that is traumatic for the patient and expensive for the payer. This review examines the literature for evidence to support the possibility that fibronectins and BMPs could be coated on the implants as part of the manufacturing process so that the proteins could be released into the tissue surrounding the implant and improve the rate of successful implantation. Full article

32 pages, 6145 KiB

Open AccessReview

Targeted Stimuli-Responsive Mesoporous Silica Nanoparticles for Bacterial Infection Treatment

by Montserrat Colilla and María Vallet-Regí

Int. J. Mol. Sci. 2020, 21(22), 8605; https://doi.org/10.3390/ijms21228605 - 15 Nov 2020

Cited by 60 | Viewed by 7424

Abstract

The rise of antibiotic resistance and the growing number of biofilm-related infections make bacterial infections a serious threat for global human health. Nanomedicine has entered into this scenario by bringing new alternatives to design and develop effective antimicrobial nanoweapons to fight against bacterial [...] Read more.

The rise of antibiotic resistance and the growing number of biofilm-related infections make bacterial infections a serious threat for global human health. Nanomedicine has entered into this scenario by bringing new alternatives to design and develop effective antimicrobial nanoweapons to fight against bacterial infection. Among them, mesoporous silica nanoparticles (MSNs) exhibit unique characteristics that make them ideal nanocarriers to load, protect and transport antimicrobial cargoes to the target bacteria and/or biofilm, and release them in response to certain stimuli. The combination of infection-targeting and stimuli-responsive drug delivery capabilities aims to increase the specificity and efficacy of antimicrobial treatment and prevent undesirable side effects, becoming a ground-breaking alternative to conventional antibiotic treatments. This review focuses on the scientific advances developed to date in MSNs for infection-targeted stimuli-responsive antimicrobials delivery. The targeting strategies for specific recognition of bacteria are detailed. Moreover, the possibility of incorporating anti-biofilm agents with MSNs aimed at promoting biofilm penetrability is overviewed. Finally, a comprehensive description of the different scientific approaches for the design and development of smart MSNs able to release the antimicrobial payloads at the infection site in response to internal or external stimuli is provided. Full article

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14 pages, 2624 KiB

Open AccessArticle

Light Energy Dose and Photosensitizer Concentration Are Determinants of Effective Photo-Killing against Caries-Related Biofilms

by Abdulrahman A. Balhaddad, Mohammed S. AlQranei, Maria S. Ibrahim, Michael D. Weir, Frederico C. Martinho, Hockin H. K. Xu and Mary Anne S. Melo

Int. J. Mol. Sci. 2020, 21(20), 7612; https://doi.org/10.3390/ijms21207612 - 15 Oct 2020

Cited by 18 | Viewed by 3078

Abstract

Caries-related biofilms and associated complications are significant threats in dentistry, especially when biofilms grow over dental restorations. The inhibition of cariogenic biofilm associated with the onset of carious lesions is crucial for preventing disease recurrence after treatment. This in vitro study defined optimized [...] Read more.

Caries-related biofilms and associated complications are significant threats in dentistry, especially when biofilms grow over dental restorations. The inhibition of cariogenic biofilm associated with the onset of carious lesions is crucial for preventing disease recurrence after treatment. This in vitro study defined optimized parameters for using a photosensitizer, toluidine blue O (TBO), activated via a red light-emitting diode (LED)-based wireless device to control the growth of cariogenic biofilms. The effect of TBO concentrations (50, 100, 150, and 200 μg/mL) exposed to light or incubated in the dark was investigated in successive cytotoxicity assays. Then, a mature Streptococcus mutans biofilm model under sucrose challenge was treated with different TBO concentrations (50, 100, and 150 μg/mL), different light energy doses (36, 108, and 180 J/cm²), and different incubation times before irradiation (1, 3, and 5 min). The untreated biofilm, irradiation with no TBO, and TBO incubation with no activation represented the controls. After treatments, biofilms were analyzed via S. mutans colony-forming units (CFUs) and live/dead assay. The percentage of cell viability was within the normal range compared to the control when 50 and 100 μg/mL of TBO were used. Increasing the TBO concentration and energy dose was associated with biofilm inhibition (p < 0.001), while increasing incubation time did not contribute to bacterial elimination (p > 0.05). Irradiating the S. mutans biofilm via 100 μg/mL of TBO and ≈180 J/cm² energy dose resulted in ≈3-log reduction and a higher amount of dead/compromised S. mutans colonies in live/dead assay compared to the control (p < 0.001). The light energy dose and TBO concentration optimized the bacterial elimination of S. mutans biofilms. These results provide a perspective on the determining parameters for highly effective photo-killing of caries-related biofilms and display the limitations imposed by the toxicity of the antibacterial photodynamic therapy’s chemical components. Future studies should support investigations on new approaches to improve or overcome the constraints of opportunities offered by photodynamic inactivation of caries-related biofilms. Full article

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19 pages, 6324 KiB

Open AccessArticle

Air-Jet Spun Corn Zein Nanofibers and Thin Films with Topical Drug for Medical Applications

by Christopher R. Gough, Kristen Bessette, Ye Xue, Xiaoyang Mou and Xiao Hu

Int. J. Mol. Sci. 2020, 21(16), 5780; https://doi.org/10.3390/ijms21165780 - 12 Aug 2020

Cited by 10 | Viewed by 5647

Abstract

Diabetic patients are especially susceptible to chronic wounds of the skin, which can lead to serious complications. Sodium citrate is one potential therapeutic molecule for the topical treatment of diabetic ulcers, but its viability requires the assistance of a biomaterial matrix. In this [...] Read more.

Diabetic patients are especially susceptible to chronic wounds of the skin, which can lead to serious complications. Sodium citrate is one potential therapeutic molecule for the topical treatment of diabetic ulcers, but its viability requires the assistance of a biomaterial matrix. In this study, nanofibers and thin films fabricated from natural corn zein protein are explored as a drug delivery vehicle for the topical drug delivery of sodium citrate. Corn zein is cheap and abundant in nature, and easily extracted with high purity, while nanofibers are frequently cited as ideal drug carriers due to their high surface area and high porosity. To further reduce costs, the 1-D nanofibers in this study were fabricated through an air jet-spinning method rather than the conventional electrospinning method. Thin films were also created as a comparative 2-D material. Corn zein composite nanofibers and thin films with different concentration of sodium citrate (1–30%) were analyzed through FTIR, DSC, TGA, and SEM. Results reveal that nanofibers are a much more effective vehicle than films, with the ability to interact with sodium citrate. Thermal analysis results show a stable material with low degradation, while FTIR reveals strong control over the protein secondary structures and hold of citrate. These tunable properties and morphologies allow the fibers to provide a sustained release of citrate and then revert to their structure prior to citrate loading. A statistical analysis via t-test confirmed a significant difference between fiber and film drug release. A biocompatibility study also confirms that cells are much more tolerant of the porous nanofiber structure than the nonporous protein films, and lower percentages of sodium citrate (1–5%) were outperformed to higher percentages (15–30%). This study demonstrated that protein-based nanofiber materials have high potential as vehicles for the delivery of topical diabetic drugs. Full article

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14 pages, 3568 KiB

Open AccessArticle

A Clean and Tunable Mussel-Inspired Coating Technology by Enzymatic Deposition of Pseudo-Polydopamine (ψ-PDA) Thin Films from Tyramine

by Maria Laura Alfieri, Lucia Panzella, Youri Arntz, Alessandra Napolitano, Vincent Ball and Marco d’Ischia

Int. J. Mol. Sci. 2020, 21(14), 4873; https://doi.org/10.3390/ijms21144873 - 10 Jul 2020

Cited by 11 | Viewed by 3608

Abstract

The tyrosinase-catalyzed oxidation of tyramine, leading to the deposition of pseudo-polydopamine (ψ-PDA) thin films, is disclosed herein as a superior technology for surface functionalization and coating at a neutral pH and at a low substrate concentration, compared to the standard autoxidative PDA coating [...] Read more.

The tyrosinase-catalyzed oxidation of tyramine, leading to the deposition of pseudo-polydopamine (ψ-PDA) thin films, is disclosed herein as a superior technology for surface functionalization and coating at a neutral pH and at a low substrate concentration, compared to the standard autoxidative PDA coating protocols. Smooth ψ-PDA thin films of variable thickness up to 87 nm were obtained from 1 mM tyramine by varying tyrosinase concentrations (5–100 U/mL). Compared to the PDA films obtained by the similar enzymatic oxidation of 1 mM dopamine with tyrosinase (T-PDA), ψ-PDA displayed slower deposition kinetics, lower water contact angles in the range of 11°–28°, denoting higher hydrophilicity but similar UV-vis absorption profiles, as well as electrochemical properties and antioxidant activity. MALDI-MS analysis indicated for ψ-PDA a well defined pattern of peaks compatible with dopamine tetrameric structures degraded to a variable extent. The exposure to a tyramine solution of tyrosinase-loaded alginate spheres, or films deposited on glass or polyethylene, resulted in a rapid gel-confined ψ-PDA formation with no leakage or darkening of the solution, allowing the complete recovery and re-utilization of the unreacted tyramine. In contrast, an abundant PDA precipitation outside the gel was observed with dopamine under the same conditions. The ψ-PDA deposition by tyrosinase-catalyzed tyramine oxidation is thus proposed as a controllable and low-waste technology for selective surface functionalization and coating or for clean eumelanin particle production. Full article

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39 pages, 4382 KiB

Open AccessReview

Stimuli-Responsive Materials for Tissue Engineering and Drug Delivery

by Sofia Municoy, María I. Álvarez Echazú, Pablo E. Antezana, Juan M. Galdopórpora, Christian Olivetti, Andrea M. Mebert, María L. Foglia, María V. Tuttolomondo, Gisela S. Alvarez, John G. Hardy and Martin F. Desimone

Int. J. Mol. Sci. 2020, 21(13), 4724; https://doi.org/10.3390/ijms21134724 - 2 Jul 2020

Cited by 134 | Viewed by 10419

Abstract

Smart or stimuli-responsive materials are an emerging class of materials used for tissue engineering and drug delivery. A variety of stimuli (including temperature, pH, redox-state, light, and magnet fields) are being investigated for their potential to change a material’s properties, interactions, structure, and/or [...] Read more.

Smart or stimuli-responsive materials are an emerging class of materials used for tissue engineering and drug delivery. A variety of stimuli (including temperature, pH, redox-state, light, and magnet fields) are being investigated for their potential to change a material’s properties, interactions, structure, and/or dimensions. The specificity of stimuli response, and ability to respond to endogenous cues inherently present in living systems provide possibilities to develop novel tissue engineering and drug delivery strategies (for example materials composed of stimuli responsive polymers that self-assemble or undergo phase transitions or morphology transformations). Herein, smart materials as controlled drug release vehicles for tissue engineering are described, highlighting their potential for the delivery of precise quantities of drugs at specific locations and times promoting the controlled repair or remodeling of tissues. Full article

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18 pages, 4703 KiB

Open AccessArticle

Studies on the Mechanisms of Anti-Inflammatory Activity of Heparin- and Hyaluronan-Containing Multilayer Coatings—Targeting NF-κB Signalling Pathway

by Hala Alkhoury, Adrian Hautmann, Bodo Fuhrmann, Frank Syrowatka, Frank Erdmann, Guoying Zhou, Sanja Stojanović, Stevo Najman and Thomas Groth

Int. J. Mol. Sci. 2020, 21(10), 3724; https://doi.org/10.3390/ijms21103724 - 25 May 2020

Cited by 18 | Viewed by 8025

Abstract

The use of implants can be hampered by chronic inflammatory reactions, which may result in failure of the implanted device. To prevent such an outcome, the present study examines the anti-inflammatory properties of surface coatings made of either hyaluronic acid (HA) or heparin [...] Read more.

The use of implants can be hampered by chronic inflammatory reactions, which may result in failure of the implanted device. To prevent such an outcome, the present study examines the anti-inflammatory properties of surface coatings made of either hyaluronic acid (HA) or heparin (Hep) in combination with chitosan (Chi) prepared as multilayers through the layer-by-layer (LbL) technique. The properties of glycosaminoglycan (GAG)-modified surfaces were characterized in terms of surface topography, thickness and wettability. Results showed a higher thickness and hydrophilicity after multilayer formation compared to poly (ethylene imine) control samples. Moreover, multilayers containing either HA or Hep dampened the inflammatory response visible by reduced adhesion, formation of multinucleated giant cells (MNGCs) and IL-1β release, which was studied using THP-1 derived macrophages. Furthermore, investigations regarding the mechanism of anti-inflammatory activity of GAG were focused on nuclear transcription factor-кB (NF-κB)-related signal transduction. Immunofluorescence staining of the p65 subunit of NF-κB and immunoblotting were performed that showed a significant decrease in NF-κB level in macrophages on GAG-based multilayers. Additionally, the association of FITC-labelled GAG was evaluated by confocal laser scanning microscopy and flow cytometry showing that macrophages were able to associate with and take up HA and Hep. Overall, the Hep-based multilayers demonstrated the most suppressive effect making this system most promising to control macrophage activation after implantation of medical devices. The results provide an insight on the anti-inflammatory effects of GAG not only based on their physicochemical properties, but also related to their mechanism of action toward NF-κB signal transduction. Full article

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15 pages, 4645 KiB

Open AccessArticle

Fabrication of Mechanically Reinforced Gelatin/Hydroxyapatite Bio-Composite Scaffolds by Core/Shell Nozzle Printing for Bone Tissue Engineering

by Haeri Kim, Hanjun Hwangbo, YoungWon Koo and GeunHyung Kim

Int. J. Mol. Sci. 2020, 21(9), 3401; https://doi.org/10.3390/ijms21093401 - 11 May 2020

Cited by 31 | Viewed by 6575

Abstract

In tissue engineering, biocompatible scaffolds are used as 3D cell niches to provide a similar environment to that of native tissue for seeded cells to regenerate the target tissue. When engineering bone tissue, high mechanical strength and calcium phosphate composition are essential factors [...] Read more.

In tissue engineering, biocompatible scaffolds are used as 3D cell niches to provide a similar environment to that of native tissue for seeded cells to regenerate the target tissue. When engineering bone tissue, high mechanical strength and calcium phosphate composition are essential factors to consider. In this study, we fabricated biocompatible composite scaffolds composed of synthetic polymers (polycaprolactone (PCL) and poly (vinyl alcohol) (PVA)), natural polymers (gelatin and collagen) and bioceramic (hydroxyapatite; HA) for bone tissue engineering. The synthetic polymers were used to enhance the mechanical properties of the composite scaffolds while the natural protein-based polymers were used to enhance various cellular activities, such as cell adhesion and proliferation. Meanwhile, the bioceramic was introduced to promote osteogenic differentiation. Composite scaffolds were evaluated for their physical characteristics, such as mechanical, swelling and protein absorbing properties as well as biological properties (cell proliferation, alkaline phosphatase (ALP) activities and calcium deposition) with human osteoblast-like cells (MG63). Consequently, incorporation of hydroxyapatite into the gelatin/PVA (C-GPH) scaffold showed 5-fold and 1.5-fold increase in calcium deposition and ALP activities, respectively compared to gelatin/PVA scaffold (C-GP). Moreover, compressive modulus also increased 1.8-fold. Integration of PCL core into gelatin/PVA/hydroxyapatite scaffold (C-PGPH) further amplified the compressive modulus 1.5-fold. In conclusion, the scaffold that is reinforced with HA particles and integrated with PCL core of the struts showed significant potential in field of bone tissue engineering. Full article

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23 pages, 8151 KiB

Open AccessArticle

Preparation of Peptide and Recombinant Tissue Plasminogen Activator Conjugated Poly(Lactic-Co-Glycolic Acid) (PLGA) Magnetic Nanoparticles for Dual Targeted Thrombolytic Therapy

by Huai-An Chen, Yunn-Hwa Ma, Tzu-Yuan Hsu and Jyh-Ping Chen

Int. J. Mol. Sci. 2020, 21(8), 2690; https://doi.org/10.3390/ijms21082690 - 13 Apr 2020

Cited by 46 | Viewed by 5303

Abstract

Recombinant tissue plasminogen activator (rtPA) is the only thrombolytic agent that has been approved by the FDA for treatment of ischemic stroke. However, a high dose intravenous infusion is required to maintain effective drug concentration, owing to the short half-life of the thrombolytic [...] Read more.

Recombinant tissue plasminogen activator (rtPA) is the only thrombolytic agent that has been approved by the FDA for treatment of ischemic stroke. However, a high dose intravenous infusion is required to maintain effective drug concentration, owing to the short half-life of the thrombolytic drug, whereas a momentous limitation is the risk of bleeding. We envision a dual targeted strategy for rtPA delivery will be feasible to minimize the required dose of rtPA for treatment. For this purpose, rtPA and fibrin-avid peptide were co-immobilized to poly(lactic-co-glycolic acid) (PLGA) magnetic nanoparticles (PMNP) to prepare peptide/rtPA conjugated PMNPs (pPMNP-rtPA). During preparation, PMNP was first surface modified with avidin, which could interact with biotin. This is followed by binding PMNP-avidin with biotin-PEG-rtPA (or biotin-PEG-peptide), which was prepared beforehand by binding rtPA (or peptide) to biotin-PEG-maleimide while using click chemistry between maleimide and the single –SH group in rtPA (or peptide). The physicochemical property characterization indicated the successful preparation of the magnetic nanoparticles with full retention of rtPA fibrinolysis activity, while biological response studies underlined the high biocompatibility of all magnetic nanoparticles from cytotoxicity and hemolysis assays in vitro. The magnetic guidance and fibrin binding effects were also confirmed, which led to a higher thrombolysis rate in vitro using PMNP-rtPA or pPMNP-rtPA when compared to free rtPA after static or dynamic incubation with blood clots. Using pressure-dependent clot lysis model in a flow system, dual targeted pPMNP-rtPA could reduce the clot lysis time for reperfusion by 40% when compared to free rtPA at the same drug dosage. From in vivo targeted thrombolysis in a rat embolic model, pPMNP-rtPA was used at 20% of free rtPA dosage to restore the iliac blood flow in vascular thrombus that was created by injecting a blood clot to the hind limb area. Full article

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16 pages, 3859 KiB

Open AccessArticle

Surface Functionalization with Polyethylene Glycol and Polyethyleneimine Improves the Performance of Graphene-Based Materials for Safe and Efficient Intracellular Delivery by Laser-Induced Photoporation

by Jing Liu, Chengnan Li, Toon Brans, Aranit Harizaj, Shana Van de Steene, Thomas De Beer, Stefaan De Smedt, Sabine Szunerits, Rabah Boukherroub, Ranhua Xiong and Kevin Braeckmans

Int. J. Mol. Sci. 2020, 21(4), 1540; https://doi.org/10.3390/ijms21041540 - 24 Feb 2020

Cited by 23 | Viewed by 5627

Abstract

Nanoparticle mediated laser-induced photoporation is a physical cell membrane disruption approach to directly deliver extrinsic molecules into living cells, which is particularly promising in applications for both adherent and suspension cells. In this work, we explored surface modifications of graphene quantum dots (GQD) [...] Read more.

Nanoparticle mediated laser-induced photoporation is a physical cell membrane disruption approach to directly deliver extrinsic molecules into living cells, which is particularly promising in applications for both adherent and suspension cells. In this work, we explored surface modifications of graphene quantum dots (GQD) and reduced graphene oxide (rGO) with polyethylene glycol (PEG) and polyethyleneimine (PEI) to enhance colloidal stability while retaining photoporation functionality. After photoporation with FITC-dextran 10 kDa (FD10), the percentage of positive HeLa cells (81% for GQD-PEG, 74% for rGO-PEG and 90% for rGO-PEI) increased approximately two-fold compared to the bare nanomaterials. While for Jurkat suspension cells, the photoporation efficiency with polymer-modified graphene-based nanomaterial reached as high as 80%. Cell viability was >80% in all these cases. In addition, polymer functionalization proved to be beneficial for the delivery of larger macromolecules (FD70 and FD500) as well. Finally, we show that rGO is suitable for photoporation using a near-infrared laser to reach 80% FD10 positive HeLa cells at 80% cell viability. We conclude that modification of graphene-based nanoparticles with PEG and especially PEI provide better colloidal stability in cell medium, resulting in more uniform transfection and overall increased efficiency. Full article

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17 pages, 3932 KiB

Open AccessArticle

Topical Drug Delivery Systems Based on Bacterial Nanocellulose: Accelerated Stability Testing

by Nuno H. C. S. Silva, Joana P. Mota, Tânia Santos de Almeida, João P. F. Carvalho, Armando J. D. Silvestre, Carla Vilela, Catarina Rosado and Carmen S. R. Freire

Int. J. Mol. Sci. 2020, 21(4), 1262; https://doi.org/10.3390/ijms21041262 - 13 Feb 2020

Cited by 42 | Viewed by 5503

Abstract

Bacterial nanocellulose (BNC) membranes have enormous potential as systems for topical drug delivery due to their intrinsic biocompatibility and three-dimensional nanoporous structure, which can house all kinds of active pharmaceutical ingredients (APIs). Thus, the present study investigated the long-term storage stability of BNC [...] Read more.

Bacterial nanocellulose (BNC) membranes have enormous potential as systems for topical drug delivery due to their intrinsic biocompatibility and three-dimensional nanoporous structure, which can house all kinds of active pharmaceutical ingredients (APIs). Thus, the present study investigated the long-term storage stability of BNC membranes loaded with both hydrophilic and lipophilic APIs, namely, caffeine, lidocaine, ibuprofen and diclofenac. The storage stability was evaluated under accelerated testing conditions at different temperatures and relative humidity (RH), i.e., 75% RH/40 °C, 60% RH/25 °C and 0% RH/40 °C. All systems were quite stable under these storage conditions with no significant structural and morphological changes or variations in the drug release profile. The only difference observed was in the moisture-uptake, which increased with RH due to the hydrophilic nature of BNC. Furthermore, the caffeine-loaded BNC membrane was selected for in vivo cutaneous compatibility studies, where patches were applied in the volar forearm of twenty volunteers for 24 h. The cutaneous responses were assessed by non-invasive measurements and the tests revealed good compatibility for caffeine-loaded BNC membranes. These results highlight the good storage stability of the API-loaded BNC membranes and their cutaneous compatibility, which confirms the real potential of these dermal delivery systems. Full article

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20 pages, 8214 KiB

Open AccessArticle

Preparation and Characterization of Surface Heat Sintered Nanohydroxyapatite and Nanowhitlockite Embedded Poly (Lactic-co-glycolic Acid) Microsphere Bone Graft Scaffolds: In Vitro and in Vivo Studies

by Gils Jose, K.T. Shalumon, Han-Tsung Liao, Chang-Yi Kuo and Jyh-Ping Chen

Int. J. Mol. Sci. 2020, 21(2), 528; https://doi.org/10.3390/ijms21020528 - 14 Jan 2020

Cited by 16 | Viewed by 4614

Abstract

In the context of using bone graft materials to restore and improve the function of damaged bone tissues, macroporous biodegradable composite bone graft scaffolds have osteoinductive properties that allow them to provide a suitable environment for bone regeneration. Hydroxyapatite (HAP) and whitlockite (WLKT) [...] Read more.

In the context of using bone graft materials to restore and improve the function of damaged bone tissues, macroporous biodegradable composite bone graft scaffolds have osteoinductive properties that allow them to provide a suitable environment for bone regeneration. Hydroxyapatite (HAP) and whitlockite (WLKT) are the two major components of hard tissues such as bone and teeth. Because of their biocompatibility and osteoinductivity, we synthesized HAP (nHAP) and WLKT nanoparticles (nWLKT) by using the chemical precipitation method. The nanoparticles were separately incorporated within poly (lactic-co-glycolic acid) (PLGA) microspheres. Following this, the composite microspheres were converted to macroporous bone grafts with sufficient mechanical strength in pin or screw shape through surface sintering. We characterized physico-chemical and mechanical properties of the nanoparticles and composites. The biocompatibility of the grafts was further tested through in vitro cell adhesion and proliferation studies using rabbit bone marrow stem cells. The ability to promote osteogenic differentiation was tested through alkaline phosphate activity and immunofluorescence staining of bone marker proteins. For in vivo study, the bone pins were implanted in tibia bone defects in rabbits to compare the bone regeneration ability though H&E, Masson’s trichrome and immunohistochemical staining. The results revealed similar physico-chemical characteristics and cellular response of PLGA/nHAP and PLGA/nWLKT scaffolds but the latter is associated with higher osteogenic potential towards BMSCs, pointing out the possibility to use this ceramic nanoparticle to prepare a sintered composite microsphere scaffold for potential bone grafts and tissue engineered implants. Full article

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2019

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25 pages, 4609 KiB

Open AccessReview

Protein and Polysaccharide-Based Magnetic Composite Materials for Medical Applications

by Elizabeth J. Bealer, Kyril Kavetsky, Sierra Dutko, Samuel Lofland and Xiao Hu

Int. J. Mol. Sci. 2020, 21(1), 186; https://doi.org/10.3390/ijms21010186 - 26 Dec 2019

Cited by 45 | Viewed by 8961

Abstract

The combination of protein and polysaccharides with magnetic materials has been implemented in biomedical applications for decades. Proteins such as silk, collagen, and elastin and polysaccharides such as chitosan, cellulose, and alginate have been heavily used in composite biomaterials. The wide diversity in [...] Read more.

The combination of protein and polysaccharides with magnetic materials has been implemented in biomedical applications for decades. Proteins such as silk, collagen, and elastin and polysaccharides such as chitosan, cellulose, and alginate have been heavily used in composite biomaterials. The wide diversity in the structure of the materials including their primary monomer/amino acid sequences allow for tunable properties. Various types of these composites are highly regarded due to their biocompatible, thermal, and mechanical properties while retaining their biological characteristics. This review provides information on protein and polysaccharide materials combined with magnetic elements in the biomedical space showcasing the materials used, fabrication methods, and their subsequent applications in biomedical research. Full article

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20 pages, 7456 KiB

Open AccessArticle

In Situ Synthesis of MIL-100(Fe) at the Surface of Fe₃O₄@AC as Highly Efficient Dye Adsorbing Nanocomposite

by Asma Hamedi, Francesco Trotta, Mahmood Borhani Zarandi, Marco Zanetti, Fabrizio Caldera, Anastasia Anceschi and Mohammad Reza Nateghi

Int. J. Mol. Sci. 2019, 20(22), 5612; https://doi.org/10.3390/ijms20225612 - 9 Nov 2019

Cited by 43 | Viewed by 5742

Abstract

A new magnetic nanocomposite called MIL-100(Fe) @Fe₃O₄@AC was synthesized by the hydrothermal method as a stable adsorbent for the removal of Rhodamine B (RhB) dye from aqueous medium. In this work, in order to increase the carbon uptake capacity, [...] Read more.

A new magnetic nanocomposite called MIL-100(Fe) @Fe₃O₄@AC was synthesized by the hydrothermal method as a stable adsorbent for the removal of Rhodamine B (RhB) dye from aqueous medium. In this work, in order to increase the carbon uptake capacity, magnetic carbon was first synthesized and then the Fe₃O₄ was used as the iron (III) supplier to synthesize MIL-100(Fe). The size of these nanocomposite is about 30–50 nm. Compared with activated charcoal (AC) and magnetic activated charcoal (Fe₃O₄@AC) nanoparticles, the surface area of MIL-100(Fe) @Fe₃O₄@AC were eminently increased while the magnetic property of this adsorbent was decreased. The surface area of AC, Fe₃O₄@AC, and MIL-100(Fe) @Fe₃O₄@AC was 121, 351, and 620 m²/g, respectively. The magnetic and thermal property, chemical structure, and morphology of the MIL-100(Fe) @Fe₃O₄@AC were considered by vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), zeta potential, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Brunner-Emmet-Teller (BET), and transmission electron microscopy (TEM) analyses. The relatively high adsorption capacity was obtained at about 769.23 mg/g compared to other adsorbents to eliminate RhB dye from the aqueous solution within 40 min. Studies of adsorption kinetics and isotherms showed that RhB adsorption conformed the Langmuir isotherm model and the pseudo second-order kinetic model. Thermodynamic amounts depicted that the RhB adsorption was spontaneous and exothermic process. In addition, the obtained nanocomposite exhibited good reusability after several cycles. All experimental results showed that MIL-100(Fe) @Fe₃O₄@AC could be a prospective sorbent for the treatment of dye wastewater. Full article

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16 pages, 2008 KiB

Open AccessReview

Astrochemistry and Astrobiology: Materials Science in Wonderland?

by Marco d’Ischia, Paola Manini, Marco Moracci, Raffaele Saladino, Vincent Ball, Helmut Thissen, Richard A. Evans, Cristina Puzzarini and Vincenzo Barone

Int. J. Mol. Sci. 2019, 20(17), 4079; https://doi.org/10.3390/ijms20174079 - 21 Aug 2019

Cited by 30 | Viewed by 8090

Abstract

Astrochemistry and astrobiology, the fascinating disciplines that strive to unravel the origin of life, have opened unprecedented and unpredicted vistas into exotic compounds as well as extreme or complex reaction conditions of potential relevance for a broad variety of applications. Representative, and so [...] Read more.

Astrochemistry and astrobiology, the fascinating disciplines that strive to unravel the origin of life, have opened unprecedented and unpredicted vistas into exotic compounds as well as extreme or complex reaction conditions of potential relevance for a broad variety of applications. Representative, and so far little explored sources of inspiration include complex organic systems, such as polycyclic aromatic hydrocarbons (PAHs) and their derivatives; hydrogen cyanide (HCN) and formamide (HCONH₂) oligomers and polymers, like aminomalononitrile (AMN)-derived species; and exotic processes, such as solid-state photoreactions on mineral surfaces, phosphorylation by minerals, cold ice irradiation and proton bombardment, and thermal transformations in fumaroles. In addition, meteorites and minerals like forsterite, which dominate dust chemistry in the interstellar medium, may open new avenues for the discovery of innovative catalytic processes and unconventional methodologies. The aim of this review was to offer concise and inspiring, rather than comprehensive, examples of astrochemistry-related materials and systems that may be of relevance in areas such as surface functionalization, nanostructures, and hybrid material design, and for innovative technological solutions. The potential of computational methods to predict new properties from spectroscopic data and to assess plausible reaction pathways on both kinetic and thermodynamic grounds has also been highlighted. Full article

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18 pages, 3386 KiB

Open AccessReview

Nanomaterials as Promising Alternative in the Infection Treatment

by María Vallet-Regí, Blanca González and Isabel Izquierdo-Barba

Int. J. Mol. Sci. 2019, 20(15), 3806; https://doi.org/10.3390/ijms20153806 - 4 Aug 2019

Cited by 131 | Viewed by 8146

Abstract

Both the prevalence of antibiotic resistance and the increased biofilm-associated infections are boosting the demand for new advanced and more effective treatment for such infections. In this sense, nanotechnology offers a ground-breaking platform for addressing this challenge. This review shows the current progress [...] Read more.

Both the prevalence of antibiotic resistance and the increased biofilm-associated infections are boosting the demand for new advanced and more effective treatment for such infections. In this sense, nanotechnology offers a ground-breaking platform for addressing this challenge. This review shows the current progress in the field of antimicrobial inorganic-based nanomaterials and their activity against bacteria and bacterial biofilm. Herein, nanomaterials preventing the bacteria adhesion and nanomaterials treating the infection once formed are presented through a classification based on their functionality. To fight infection, nanoparticles with inherent antibacterial activity and nanoparticles acting as nanovehicles are described, emphasizing the design of the carrier nanosystems with properties targeting the bacteria and the biofilm. Full article

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12 pages, 2264 KiB

Open AccessArticle

The Effect of the Repression of Oxidative Stress on Tenocyte Differentiation: A Preliminary Study of a Rat Cell Model Using a Novel Differential Tensile Strain Bioreactor

by Ming-Yen Hsiao, Ping-Cheng Lin, Wei-Hao Liao, Wen-Shiang Chen, Chia-Hsien Hsu, Cheng-Kun He, Ya-Wen Wu, Amit Gefen, Michele Iafisco, Lixin Liu and Feng-Huei Lin

Int. J. Mol. Sci. 2019, 20(14), 3437; https://doi.org/10.3390/ijms20143437 - 12 Jul 2019

Cited by 13 | Viewed by 3833

Abstract

Because of limitations in the current understanding of the exact pathogenesis of tendinopathy, and the lack of an optimal experimental model, effective therapy for the disease is currently unavailable. This study aims to prove that repression of oxidative stress modulates the differentiation of [...] Read more.

Because of limitations in the current understanding of the exact pathogenesis of tendinopathy, and the lack of an optimal experimental model, effective therapy for the disease is currently unavailable. This study aims to prove that repression of oxidative stress modulates the differentiation of tendon-derived cells (TDCs) sustaining excessive tensile strains, and proposes a novel bioreactor capable of applying differential tensile strains to cultured cells simultaneously. TDCs, including tendon-derived stem cells, tenoblasts, tenocytes, and fibroblasts, were isolated from the patellar tendons of Sprague‒Dawley rats. Cyclic uniaxial stretching with 4% or 8% strain at 0.5 Hz for 8 h was applied to TDCs. TDCs subjected to 8% strain were treated with epigallocatechin gallate (EGCG), piracetam, or no medication. Genes representing non-tenocyte lineage (Pparg, Sox9, and Runx2) and type I and type III collagen were analyzed by quantitative polymerase chain reaction. The 8% strain group showed increased expression of non-tenocyte lineage genes and type III/type I collagen ratios compared with the control and 4% strain groups, and the increased expression was ameliorated with addition of EGCG and piracetam. The model developed in this work could be applied to future research on the pathophysiology of tendinopathy and development of treatment options for the disease. Repression of oxidative stress diminishes the expression of genes indicating aberrant differentiation in a rat cell model, which indicates potential therapeutic intervention of tendinopathy, the often relentlessly degenerate condition. Full article

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14 pages, 2962 KiB

Open AccessArticle

The Effect of Molecular Weight on the Antibacterial Activity of N,N,N-Trimethyl Chitosan (TMC)

by Priyanka Sahariah, Dorota Cibor, Dorota Zielińska, Martha Á. Hjálmarsdóttir, Dawid Stawski and Már Másson

Int. J. Mol. Sci. 2019, 20(7), 1743; https://doi.org/10.3390/ijms20071743 - 9 Apr 2019

Cited by 46 | Viewed by 5765

Abstract

N,N,N-trimethyl chitosan (TMC) with 93% degree of trimethylation was synthesized. TMC and the chitosan starting material were subjected to acidic hydrolysis to produce 49 different samples with a reduced average molecular weight (M_w) ranging from 2 [...] Read more.

N,N,N-trimethyl chitosan (TMC) with 93% degree of trimethylation was synthesized. TMC and the chitosan starting material were subjected to acidic hydrolysis to produce 49 different samples with a reduced average molecular weight (M_w) ranging from 2 to 144 kDa. This was done to allow the investigation of the relationship between antibacterial activity and M_w over a wide M_w range. NMR investigation showed that hydrolysis did not affect the degree of trimethylation (DS_TRI) or the structure of the polymer backbone. The activity of TMC against Staphylococcus aureus (S. aureus) increased sharply with M_w until a certain M_w value (critical M_w for high activity, CMW) was reached. After the CMW, the activity was not affected by a further increase in the M_w. A similar pattern of activity was observed for chitosan. The CMW was determined to be 20 kDa for TMC and 50 kDa for chitosan. Full article

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18 pages, 2637 KiB

Open AccessReview

Bioengineered Skin Intended for Skin Disease Modeling

by Maria Sarkiri, Stephan C. Fox, Lidy E. Fratila-Apachitei and Amir A. Zadpoor

Int. J. Mol. Sci. 2019, 20(6), 1407; https://doi.org/10.3390/ijms20061407 - 20 Mar 2019

Cited by 28 | Viewed by 7115

Abstract

Clinical use of bioengineered skin in reconstructive surgery has been established for more than 30 years. The limitations and ethical considerations regarding the use of animal models have expanded the application of bioengineered skin in the areas of disease modeling and drug screening. [...] Read more.

Clinical use of bioengineered skin in reconstructive surgery has been established for more than 30 years. The limitations and ethical considerations regarding the use of animal models have expanded the application of bioengineered skin in the areas of disease modeling and drug screening. These skin models should represent the anatomical and physiological traits of native skin for the efficient replication of normal and pathological skin conditions. In addition, reliability of such models is essential for the conduction of faithful, rapid, and large-scale studies. Therefore, research efforts are focused on automated fabrication methods to replace the traditional manual approaches. This report presents an overview of the skin models applicable to skin disease modeling along with their fabrication methods, and discusses the potential of the currently available options to conform and satisfy the demands for disease modeling and drug screening. Full article

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13 pages, 6162 KiB

Open AccessArticle

Rare-Earth-Doped Calcium Carbonate Exposed to X-ray Irradiation to Induce Reactive Oxygen Species for Tumor Treatment

by Chun-Chen Yang, Wei-Yun Wang, Feng-Huei Lin and Chun-Han Hou

Int. J. Mol. Sci. 2019, 20(5), 1148; https://doi.org/10.3390/ijms20051148 - 6 Mar 2019

Cited by 15 | Viewed by 4691

Abstract

Conventional photodynamic therapy (PDT) is limited by its penetration depth due to the photosensitizer and light source. In this study, we developed X-ray induced photodynamic therapy that applied X-ray as the light source to activate Ce-doped CaCO₃ (CaCO₃:Ce) to generate [...] Read more.

Conventional photodynamic therapy (PDT) is limited by its penetration depth due to the photosensitizer and light source. In this study, we developed X-ray induced photodynamic therapy that applied X-ray as the light source to activate Ce-doped CaCO₃ (CaCO₃:Ce) to generate an intracellular reactive oxygen species (ROS) for killing cancer cells. The A549 cell line was used as the in vitro and in vivo model to evaluate the efficacy of X-ray-induced CaCO₃:Ce. The cell viability significantly decreased and cell cytotoxicity obviously increased with CaCO₃:Ce exposure under X-ray irradiation, which is less harmful than radiotherapy in tumor treatment. CaCO₃:Ce produced significant ROS under X-ray irradiation and promoted A549 cancer cell death. CaCO₃:Ce can enhance the efficacy of X-ray induced PDT, and tumor growth was inhibited in vivo. The blood analysis and hematoxylin and eosin stain (H&E) stain fully supported the safety of the treatment. The mechanisms underlying ROS and CO₂ generation by CaCO₃:Ce activated by X-ray irradiation to induce cell toxicity, thereby inhibiting tumor growth, is discussed. These findings and advances are of great importance in providing a novel therapeutic approach as an alternative tumor treatment. Full article

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30 pages, 4787 KiB

Open AccessReview

Functional Mesoporous Silica Nanocomposites: Biomedical Applications and Biosafety

by Rafael R. Castillo and María Vallet-Regí

Int. J. Mol. Sci. 2019, 20(4), 929; https://doi.org/10.3390/ijms20040929 - 20 Feb 2019

Cited by 54 | Viewed by 7452

Abstract

The rise and development of nanotechnology has enabled the creation of a wide number of systems with new and advantageous features to treat cancer. However, in many cases, the lone application of these new nanotherapeutics has proven not to be enough to achieve [...] Read more.

The rise and development of nanotechnology has enabled the creation of a wide number of systems with new and advantageous features to treat cancer. However, in many cases, the lone application of these new nanotherapeutics has proven not to be enough to achieve acceptable therapeutic efficacies. Hence, to avoid these limitations, the scientific community has embarked on the development of single formulations capable of combining functionalities. Among all possible components, silica—either solid or mesoporous—has become of importance as connecting and coating material for these new-generation therapeutic nanodevices. In the present review, the most recent examples of fully inorganic silica-based functional composites are visited, paying particular attention to those with potential biomedical applicability. Additionally, some highlights will be given with respect to their possible biosafety issues based on their chemical composition. Full article

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