Nanomaterials

Editorial

Jump to: Research, Review

2 pages, 180 KiB

Open AccessEditorial

Non-Cytotoxic Nanoparticles

by Raphaël Schneider

Nanomaterials 2022, 12(16), 2865; https://doi.org/10.3390/nano12162865 - 19 Aug 2022

Viewed by 1135

Abstract

For several decades, nanoparticles (NPs) are becoming widely used in various industries, in electronics, agriculture, textile production or medicine [...] Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

Research

Jump to: Editorial, Review

13 pages, 4715 KiB

Open AccessArticle

Biological Potential of Polyethylene Glycol (PEG)-Functionalized Graphene Quantum Dots in In Vitro Neural Stem/Progenitor Cells

by Yunseong Ji, Yu-Meng Li, Jin Gwan Seo, Tae-Su Jang, Jonathan Campbell Knowles, Sung Ho Song and Jung-Hwan Lee

Nanomaterials 2021, 11(6), 1446; https://doi.org/10.3390/nano11061446 - 29 May 2021

Cited by 31 | Viewed by 3801

Abstract

Stem cell therapy is one of the novel and prospective fields. The ability of stem cells to differentiate into different lineages makes them attractive candidates for several therapies. It is essential to understand the cell fate, distribution, and function of transplanted cells in [...] Read more.

Stem cell therapy is one of the novel and prospective fields. The ability of stem cells to differentiate into different lineages makes them attractive candidates for several therapies. It is essential to understand the cell fate, distribution, and function of transplanted cells in the local microenvironment before their applications. Therefore, it is necessary to develop an accurate and reliable labeling method of stem cells for imaging techniques to track their translocation after transplantation. The graphitic quantum dots (GQDs) are selected among various stem cell labeling and tracking strategies which have high photoluminescence ability, photostability, relatively low cytotoxicity, tunable surface functional groups, and delivering capacity. Since GQDs interact easily with the cell and interfere with cell behavior through surface functional groups, an appropriate surface modification needs to be considered to get close to the ideal labeling nanoprobes. In this study, polyethylene glycol (PEG) is used to improve biocompatibility while simultaneously maintaining the photoluminescent potentials of GQDs. The biochemically inert PEG successfully covered the surface of GQDs. The PEG-GQDs composites show adequate bioimaging capabilities when internalized into neural stem/progenitor cells (NSPCs). Furthermore, the bio-inertness of the PEG-GQDs is confirmed. Herein, we introduce the PEG-GQDs as a valuable tool for stem cell labeling and tracking for biomedical therapies in the field of neural regeneration. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Figure 1

14 pages, 5350 KiB

Open AccessArticle

Silver Nanocolloids Loaded with Betulinic Acid with Enhanced Antitumor Potential: Physicochemical Characterization and In Vitro Evaluation

by Iulia Pinzaru, Cristian Sarau, Dorina Coricovac, Iasmina Marcovici, Crinela Utescu, Sergiu Tofan, Ramona Amina Popovici, Horatiu Cristian Manea, Ioana E. Pavel, Codruta Soica and Cristina Dehelean

Nanomaterials 2021, 11(1), 152; https://doi.org/10.3390/nano11010152 - 9 Jan 2021

Cited by 9 | Viewed by 2745

Abstract

Betulinic acid (BA), a natural compound with various health benefits including selective antitumor activity, has a limited applicability in vivo due to its poor water solubility and bioavailability. Thus, this study focused on obtaining a BA nano-sized formulation with improved solubility and enhanced [...] Read more.

Betulinic acid (BA), a natural compound with various health benefits including selective antitumor activity, has a limited applicability in vivo due to its poor water solubility and bioavailability. Thus, this study focused on obtaining a BA nano-sized formulation with improved solubility and enhanced antitumor activity using silver nanocolloids (SilCo and PEG_SilCo) as drug carriers. The synthesis was performed using a chemical method and the physicochemical characterization was achieved applying UV-Vis absorption, transmission electron microscopy (TEM), Raman and photon correlation spectroscopy (PCS). The biological evaluation was conducted on two in vitro experimental models—hepatocellular carcinoma (HepG2) and lung cancer (A549) cell lines. The physicochemical characterization showed the following results: an average hydrodynamic diameter of 32 nm for SilCo_BA and 71 nm for PEG_SilCo_BA, a spherical shape, and a loading capacity of 54.1% for SilCo_BA and 61.9% for PEG_SilCo_BA, respectively. The in vitro assessment revealed a cell type- and time-dependent cytotoxic effect characterized by a decrease in cell viability as follows: (i) SilCo_BA (66.44%) < PEG_SilCo_BA (72.05%) < BA_DMSO (75.30%) in HepG2 cells, and (ii) SilCo_BA (75.28%) < PEG_SilCo_BA (86.80%) < BA_DMSO (87.99%) in A549 cells. The novel silver nanocolloids loaded with BA induced an augmented anticancer effect as compared to BA alone. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Figure 1

17 pages, 8601 KiB

Open AccessFeature PaperArticle

Temperature-Responsive Pyraclostrobin-Loaded Octadecane Submicrocapsules with Lowered Toxicity

by Aiym Tleuova, VSSL Prasad Talluri, Rohitesh Kumar and František Štěpánek

Nanomaterials 2020, 10(12), 2374; https://doi.org/10.3390/nano10122374 - 28 Nov 2020

Cited by 6 | Viewed by 2291

Abstract

Pyraclostrobin (Pyr) is one of the most effective fungicides. However, it can degrade via photolysis in water, it is toxic to aquatic life and if inhaled, it has a low solubility in water, that leads to difficulties when applying to plants by spraying. [...] Read more.

Pyraclostrobin (Pyr) is one of the most effective fungicides. However, it can degrade via photolysis in water, it is toxic to aquatic life and if inhaled, it has a low solubility in water, that leads to difficulties when applying to plants by spraying. Additionally, the necessity of repeated (weekly) sprays of fungicides when the pathogen growth risk is the highest, such as at the temperature range of 24 to 36 °C and increased humidity of about 95%, leads to loss of efficiency of the fungicide and overdose of chemicals. In the present study, pyraclostrobin was microencapsulated to solve the abovementioned issues. As a core of capsules octadecane (OD) with a melting point of 28 °C was used, thus, the release of pyraclostrobin was controlled via temperature change. Pyraclostrobin-loaded submicrocapsules (PyrSMCs) were characterized using SEM, DLS, TGA/DSC, HPLC, FTIR methods; stimuli-responsivity was tested employing in vitro tests with pathogenic culture (Fungal strain of Pyrenophora teres - CPPF-453) grown in Petri dishes. Toxicity of PyrSMCs to Artemia salina was studied as well. Size of capsules was 200–600 nm along with the presence of bigger capsules with a diameter of 1–4 µm. PyrSMCs showed excellent antifungal effects above the melting point of octadecane. PyrSMCs demonstrated 29 times less toxicity than pyraclostrobin of technical grade. Overall, results show the potential of such capsules to be applied in the agricultural industry for precise agriculture strategies. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Graphical abstract

17 pages, 3932 KiB

Open AccessArticle

NonToxic Silver/Poly-1-Vinyl-1,2,4-Triazole Nanocomposite Materials with Antibacterial Activity

by Irina A. Shurygina, Galina F. Prozorova, Irina S. Trukhan, Svetlana A. Korzhova, Tatiana V. Fadeeva, Alexander S. Pozdnyakov, Nataliya N. Dremina, Artem I. Emel’yanov, Nadezhda P. Kuznetsova and Michael G. Shurygin

Nanomaterials 2020, 10(8), 1477; https://doi.org/10.3390/nano10081477 - 28 Jul 2020

Cited by 21 | Viewed by 2943

Abstract

Novel silver/poly-1-vinyl-1,2,4-triazole nanocomposite materials—possessing antimicrobial activity against Gram-positive and Gram-negative bacteria—have been synthesized and characterized in the solid state and aqueous solution by complex of modern physical-chemical and biologic methods. TEM-monitoring has revealed the main stages of microbial cell (E. coli) [...] Read more.

Novel silver/poly-1-vinyl-1,2,4-triazole nanocomposite materials—possessing antimicrobial activity against Gram-positive and Gram-negative bacteria—have been synthesized and characterized in the solid state and aqueous solution by complex of modern physical-chemical and biologic methods. TEM-monitoring has revealed the main stages of microbial cell (E. coli) destruction by novel nanocomposite. The concept of direct polarized destruction of microbes by nanosilver proposed by the authors allows the relationship between physicochemical and antimicrobial properties of novel nanocomposites. At the same time, it was shown that the nanocomposite was nontoxic to the fibroblast cell culture. Thus, the synthesized nanocomposite combining antibacterial activity against Gram-positive and Gram-negative bacteria as well as the absence of toxic effects on mammalian cells is a promising material for the development of catheters, coatings for medical devices. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Figure 1

10 pages, 1661 KiB

Open AccessArticle

Graphene-Like Layers from Carbon Black: In Vivo Toxicity Assessment

by Marta d’Amora, Michela Alfe, Valentina Gargiulo and Silvia Giordani

Nanomaterials 2020, 10(8), 1472; https://doi.org/10.3390/nano10081472 - 27 Jul 2020

Cited by 8 | Viewed by 2819

Abstract

Graphene-like (GL) layers, a new graphene-related material (GRM), possess peculiar chemical, colloidal, optical and transport properties. Considering the very recent promising application of GL layers in biomedical and bioelectronic fields, it is of utmost importance to investigate the toxicological profile of these nanomaterials. [...] Read more.

Graphene-like (GL) layers, a new graphene-related material (GRM), possess peculiar chemical, colloidal, optical and transport properties. Considering the very recent promising application of GL layers in biomedical and bioelectronic fields, it is of utmost importance to investigate the toxicological profile of these nanomaterials. This study represents an important first report of a complete in vivo toxicity assessment of GL layers on embryonic zebrafish (Danio rerio). Our results show that GL layers do not lead to any perturbations in the different biological parameters evaluated, indicating their good biocompatibility on a vertebrate model. The new insight into the biosafety of GL layers will expand their applications in nanomedicine. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Graphical abstract

15 pages, 9685 KiB

Open AccessArticle

Cellular Responses of Human Lymphatic Endothelial Cells to Carbon Nanomaterials

by Mahoko Sano, Makoto Izumiya, Hisao Haniu, Katsuya Ueda, Kosuke Konishi, Haruka Ishida, Chika Kuroda, Takeshi Uemura, Kaoru Aoki, Yoshikazu Matsuda and Naoto Saito

Nanomaterials 2020, 10(7), 1374; https://doi.org/10.3390/nano10071374 - 14 Jul 2020

Cited by 7 | Viewed by 2733

Abstract

One of the greatest challenges to overcome in the pursuit of the medical application of carbon nanomaterials (CNMs) is safety. Particularly, when considering the use of CNMs in drug delivery systems (DDSs), evaluation of safety at the accumulation site is an essential step. [...] Read more.

One of the greatest challenges to overcome in the pursuit of the medical application of carbon nanomaterials (CNMs) is safety. Particularly, when considering the use of CNMs in drug delivery systems (DDSs), evaluation of safety at the accumulation site is an essential step. In this study, we evaluated the toxicity of carbon nanohorns (CNHs), which are potential DDSs, using human lymph node endothelial cells that have been reported to accumulate CNMs, as a comparison to fibrous, multi-walled carbon nanotubes (MWCNTs) and particulate carbon black (CB). The effect of different surface characteristics was also evaluated using two types of CNHs (untreated and oxidized). In the fibrous MWCNT, cell growth suppression, as well as expression of inflammatory cytokine genes was observed, as in previous reports. In contrast, no significant toxicity was observed for particulate CB and CNHs, which was different from the report of CB cytotoxicity in vascular endothelial cells. These results show that (1) lymph endothelial cells need to be tested separately from other endothelial cells for safety evaluation of nanomaterials, and (2) the potential of CNHs as DDSs. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Figure 1

19 pages, 18852 KiB

Open AccessArticle

A Comparative Assessment of Mechanisms and Effectiveness of Radiosensitization by Titanium Peroxide and Gold Nanoparticles

by Mennaallah Hassan, Masao Nakayama, Mohammed Salah, Hiroaki Akasaka, Hikaru Kubota, Makiko Nakahana, Tatsuichiro Tagawa, Kenta Morita, Ai Nakaoka, Takeaki Ishihara, Daisuke Miyawaki, Kenji Yoshida, Yuya Nishimura, Chiaki Ogino and Ryohei Sasaki

Nanomaterials 2020, 10(6), 1125; https://doi.org/10.3390/nano10061125 - 7 Jun 2020

Cited by 12 | Viewed by 4006

Abstract

The development of potentially safe radiosensitizing agents is essential to enhance the treatment outcomes of radioresistant cancers. The titanium peroxide nanoparticle (TiOxNP) was originally produced using the titanium dioxide nanoparticle, and it showed excellent reactive oxygen species (ROS) generation in response to ionizing [...] Read more.

The development of potentially safe radiosensitizing agents is essential to enhance the treatment outcomes of radioresistant cancers. The titanium peroxide nanoparticle (TiOxNP) was originally produced using the titanium dioxide nanoparticle, and it showed excellent reactive oxygen species (ROS) generation in response to ionizing radiation. Surface coating the TiOxNPs with polyacrylic acid (PAA) showed low toxicity to the living body and excellent radiosensitizing effect on cancer cells. Herein, we evaluated the mechanism of radiosensitization by PAA-TiOxNPs in comparison with gold nanoparticles (AuNPs) which represent high-atomic-number nanoparticles that show a radiosensitizing effect through the emission of secondary electrons. The anticancer effects of both nanoparticles were compared by induction of apoptosis, colony-forming assay, and the inhibition of tumor growth. PAA-TiOxNPs showed a significantly more radiosensitizing effect than that of AuNPs. A comparison of the types and amounts of ROS generated showed that hydrogen peroxide generation by PAA-TiOxNPs was the major factor that contributed to the nanoparticle radiosensitization. Importantly, PAA-TiOxNPs were generally nontoxic to healthy mice and caused no histological abnormalities in the liver, kidney, lung, and heart tissues. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Figure 1

18 pages, 3947 KiB

Open AccessArticle

One-Step Synthesis of Diamine-Functionalized Graphene Quantum Dots from Graphene Oxide and Their Chelating and Antioxidant Activities

by Rabeb El-Hnayn, Laetitia Canabady-Rochelle, Christophe Desmarets, Lavinia Balan, Hervé Rinnert, Olivier Joubert, Ghouti Medjahdi, Hafedh Ben Ouada and Raphaël Schneider

Nanomaterials 2020, 10(1), 104; https://doi.org/10.3390/nano10010104 - 4 Jan 2020

Cited by 44 | Viewed by 6625

Abstract

2,2’-(Ethylenedioxy)bis(ethylamine)-functionalized graphene quantum dots (GQDs) were prepared under mild conditions from graphene oxide (GO) via oxidative fragmentation. The as-prepared GQDs have an average diameter of ca. 4 nm, possess good colloidal stability, and emit strong green-yellow light with a photoluminescence (PL) quantum yield [...] Read more.

2,2’-(Ethylenedioxy)bis(ethylamine)-functionalized graphene quantum dots (GQDs) were prepared under mild conditions from graphene oxide (GO) via oxidative fragmentation. The as-prepared GQDs have an average diameter of ca. 4 nm, possess good colloidal stability, and emit strong green-yellow light with a photoluminescence (PL) quantum yield of 22% upon excitation at 375 nm. We also demonstrated that the GQDs exhibit high photostability and the PL intensity is poorly affected while tuning the pH from 1 to 8. Finally, GQDs can be used to chelate Fe(II) and Cu(II) cations, scavenge radicals, and reduce Fe(III) into Fe(II). These chelating and reducing properties that associate to the low cytotoxicity of GQDs show that these nanoparticles are of high interest as antioxidants for health applications. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Graphical abstract

19 pages, 3969 KiB

Open AccessArticle

A Novel Approach towards Synthesis and Characterization of Non-Cytotoxic Gold Nanoparticles Using Taurine as Capping Agent

by Akash Kumar, Nabojit Das, Neeraj Kumar Satija, Kapil Mandrah, Somendu Kumar Roy and Raja Gopal Rayavarapu

Nanomaterials 2020, 10(1), 45; https://doi.org/10.3390/nano10010045 - 24 Dec 2019

Cited by 26 | Viewed by 5885

Abstract

Metal gold nanoparticles are of great interest due to their unique physico-chemical properties and their potential to be used as nano-probes in biosensors, drug delivery, and therapeutic applications. Currently, many capping agents are used for metal gold nanoparticles, such as cetyltrimethylammonium bromide (CTAB) [...] Read more.

Metal gold nanoparticles are of great interest due to their unique physico-chemical properties and their potential to be used as nano-probes in biosensors, drug delivery, and therapeutic applications. Currently, many capping agents are used for metal gold nanoparticles, such as cetyltrimethylammonium bromide (CTAB) and tri-sodium citrate that have been reported to be toxic and hinders biological applications. To address this issue, we report, for the first time, the use of taurine as a stable non-cytotoxic capping agent for synthesizing gold nanoparticles by using an in situ wet-chemical method. This facile method resulted in monodisperse gold nanospheres with a high yield and stability. Monodisperse gold nanospheres with average diameters of 6.9 nm and 46 nm were synthesized at a high yield with controlled morphology. Temperature played a critical role in determining the size of the taurine-capped gold nanoparticles. The subtle changes in the reaction parameters had a tremendous effect on the final size of nanoparticles and their stability. The synthesized nanoparticles were characterized by using optical spectroscopy, a ZetaSizer, a NanoSight, Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), X-ray Photon Spectroscopy (XPS) and Electron Microscopy to understand their physico-chemical properties. Taurine was explored as a capping and stabilizing agent for gold nanospheres, which were evaluated for their toxicity responses towards human liver carcinoma cells (HepG2) via MTT assay. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Graphical abstract

14 pages, 2844 KiB

Open AccessArticle

Grouping of Poorly Soluble Low (Cyto)Toxic Particles: Example with 15 Selected Nanoparticles and A549 Human Lung Cells

by Veno Kononenko, David B. Warheit and Damjana Drobne

Nanomaterials 2019, 9(5), 704; https://doi.org/10.3390/nano9050704 - 6 May 2019

Cited by 4 | Viewed by 3495

Abstract

Poorly soluble, low (cyto)toxic particles (PSLTs) are often regarded as one group, but it is important that these particles can be further differentiated based on their bioactivity. Currently, there are no biological endpoint based groupings for inhaled nanoparticles (NPs) that would allow us [...] Read more.

Poorly soluble, low (cyto)toxic particles (PSLTs) are often regarded as one group, but it is important that these particles can be further differentiated based on their bioactivity. Currently, there are no biological endpoint based groupings for inhaled nanoparticles (NPs) that would allow us to subgroup PSLTs based on their mode of action. The aim of this study was to group NPs based on their cytotoxicity and by using the in vitro response of the endo-lysosomal system as a biological endpoint. The endo-lysosomal system is a main cellular loading site for NPs. An impaired endo-lysosomal system in alveolar type II cells may have serious adverse effects on the maintenance of pulmonary surfactant homeostasis. The 15 different NPs were tested with human lung adenocarcinoma (A549) cells. The highly soluble NPs were most cytotoxic. With respect to PSLTs, only three NPs increased the cellular load of acid and phospholipid rich organelles indicating particle biopersistence. All the rest PSLTs could be regarded as low hazardous. The presented in vitro test system could serve as a fast screening tool to group particles according to their ability to interfere with lung surfactant metabolism. We discuss the applicability of the suggested test system for bringing together substances with similar modes-of-action on lung epithelium. In addition, we discuss this approach as a benchmark test for the comparative assessment of biopersistence of PSLTs. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Figure 1

20 pages, 6445 KiB

Open AccessArticle

A Comparative Assessment of Nanotoxicity Induced by Metal (Silver, Nickel) and Metal Oxide (Cobalt, Chromium) Nanoparticles in Labeo rohita

by Zakia Kanwal, Muhammad Akram Raza, Farkhanda Manzoor, Saira Riaz, Ghazala Jabeen, Shafaq Fatima and Shahzad Naseem

Nanomaterials 2019, 9(2), 309; https://doi.org/10.3390/nano9020309 - 25 Feb 2019

Cited by 44 | Viewed by 6954

Abstract

In the present in vivo study, we provide a comparison of toxicological consequences induced by four different types of spherical nanoparticles (NPs)—silver nanoparticles (AgNPs, 40 ± 6 nm), nickel (NiNPs, 43 ± 6 nm), cobalt oxide (Co₃O₄NPs, 60 ± [...] Read more.

In the present in vivo study, we provide a comparison of toxicological consequences induced by four different types of spherical nanoparticles (NPs)—silver nanoparticles (AgNPs, 40 ± 6 nm), nickel (NiNPs, 43 ± 6 nm), cobalt oxide (Co₃O₄NPs, 60 ± 6 nm), and chromium oxide (Cr₃O₄NPs, 50 ± 5 nm)—on freshwater fish Labeo rohita. Fish were exposed to NPs (25 mg/L) for 21 days. We observed a NPs type-dependent toxicity in fish. An altered behavior showing signs of stress and a substantial reduction in total leukocyte count was noticed in all NP-treated groups. A low total erythrocyte count in all NP-treated fish except for Co₃O₄NPs was discerned while a low survival rate in the case of Cr₃O₄NP-treated fish was observed. A significant decrease in growth and hemoglobin were noticed in NiNP- and Cr₃O₄NP-treated fish. A considerable total protein elevation was detected in NiNP-, Co₃O₄NP-, and Cr₃O₄NP-treated groups. An upgrading in albumin level was witnessed in Co₃O₄NP- and Cr₃O₄NP-treated groups while a high level of globulin was noted in NiNP- and Co₃O₄NP-exposed groups. In all NP-treated groups, a depleted activity of antioxidative enzymes and pathological lesions in liver and kidney were noticed. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Figure 1

14 pages, 3273 KiB

Open AccessArticle

Preparation of Messenger RNA Nanomicelles via Non-Cytotoxic PEG-Polyamine Nanocomplex for Intracerebroventicular Delivery: A Proof-of-Concept Study in Mouse Models

by Long Yi Chan, Yit Lung Khung and Chin-Yu Lin

Nanomaterials 2019, 9(1), 67; https://doi.org/10.3390/nano9010067 - 5 Jan 2019

Cited by 22 | Viewed by 5502

Abstract

The specific delivery of messenger RNA (mRNA) is an excellent alternative to plasmid DNA, due to the latter’s potential risk for random integration into the host genome. In this study, we propose the use of specially tailored polyplex nanomicelles for the intravenous delivery [...] Read more.

The specific delivery of messenger RNA (mRNA) is an excellent alternative to plasmid DNA, due to the latter’s potential risk for random integration into the host genome. In this study, we propose the use of specially tailored polyplex nanomicelles for the intravenous delivery of mRNA into the brain of mice. In brief, along the backbone of a polyaspartamide polymer that is terminated with a 42k Polyethylene glycol chain (PEG), aminoethylene-repeating groups (two, three, and four units, respectively) were conjugated to side-chains to promote electrostatic interactions with mRNA. This structural configuration would ultimately condense into a polyplex nanomicelle ranging between 24 and 34 nm, as was confirmed by transmission electron microscopy (TEM) and dynamic light scattering (DLS) while the chemistry of the synthesis was validated through NMR analysis. Subsequently, we hypothesized an important correlation pertaining to the role of hydrogen bonding between the interaction of polyamine and mRNA in due course. As a proof of concept, we encapsulated the luciferase (Luc2) mRNA as a reporter gene through in vitro transcription (IVT) and subsequently infused the polyplex nanomicelles into mouse brains via an intracerebroventricular (ICV) injection to bypass the blood–brain barriers (BBB). Data revealed that PEGylated polyplex nanomicelles possessing four repeating units of aminoethylene groups had exhibited the best Luc2 mRNA delivery efficiency with no significant immune response registered. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Graphical abstract

Review

Jump to: Editorial, Research

34 pages, 6963 KiB

Open AccessReview

Are Titania Photocatalysts and Titanium Implants Safe? Review on the Toxicity of Titanium Compounds

by Agata Markowska-Szczupak, Maya Endo-Kimura, Oliwia Paszkiewicz and Ewa Kowalska

Nanomaterials 2020, 10(10), 2065; https://doi.org/10.3390/nano10102065 - 19 Oct 2020

Cited by 41 | Viewed by 10075

Abstract

Titanium and its compounds are broadly used in both industrial and domestic products, including jet engines, missiles, prostheses, implants, pigments, cosmetics, food, and photocatalysts for environmental purification and solar energy conversion. Although titanium/titania-containing materials are usually safe for human, animals and environment, increasing [...] Read more.

Titanium and its compounds are broadly used in both industrial and domestic products, including jet engines, missiles, prostheses, implants, pigments, cosmetics, food, and photocatalysts for environmental purification and solar energy conversion. Although titanium/titania-containing materials are usually safe for human, animals and environment, increasing concerns on their negative impacts have been postulated. Accordingly, this review covers current knowledge on the toxicity of titania and titanium, in which the behaviour, bioavailability, mechanisms of action, and environmental impacts have been discussed in detail, considering both light and dark conditions. Consequently, the following conclusions have been drawn: (i) titania photocatalysts rarely cause health and environmental problems; (ii) despite the lack of proof, the possible carcinogenicity of titania powders to humans is considered by some authorities; (iii) titanium alloys, commonly applied as implant materials, possess a relatively low health risk; (iv) titania microparticles are less toxic than nanoparticles, independent of the means of exposure; (v) excessive accumulation of titanium in the environment cannot be ignored; (vi) titanium/titania-containing products should be clearly marked with health warning labels, especially for pregnant women and young children; (vi) a key knowledge gap is the lack of comprehensive data about the environmental content and the influence of titania/titanium on biodiversity and the ecological functioning of terrestrial and aquatic ecosystems. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Graphical abstract

27 pages, 3270 KiB

Open AccessReview

Multi-Scale Surface Treatments of Titanium Implants for Rapid Osseointegration: A Review

by Qingge Wang, Peng Zhou, Shifeng Liu, Shokouh Attarilar, Robin Lok-Wang Ma, Yinsheng Zhong and Liqiang Wang

Nanomaterials 2020, 10(6), 1244; https://doi.org/10.3390/nano10061244 - 26 Jun 2020

Cited by 160 | Viewed by 9120

Abstract

The propose of this review was to summarize the advances in multi-scale surface technology of titanium implants to accelerate the osseointegration process. The several multi-scaled methods used for improving wettability, roughness, and bioactivity of implant surfaces are reviewed. In addition, macro-scale methods (e.g., [...] Read more.

The propose of this review was to summarize the advances in multi-scale surface technology of titanium implants to accelerate the osseointegration process. The several multi-scaled methods used for improving wettability, roughness, and bioactivity of implant surfaces are reviewed. In addition, macro-scale methods (e.g., 3D printing (3DP) and laser surface texturing (LST)), micro-scale (e.g., grit-blasting, acid-etching, and Sand-blasted, Large-grit, and Acid-etching (SLA)) and nano-scale methods (e.g., plasma-spraying and anodization) are also discussed, and these surfaces are known to have favorable properties in clinical applications. Functionalized coatings with organic and non-organic loadings suggest good prospects for the future of modern biotechnology. Nevertheless, because of high cost and low clinical validation, these partial coatings have not been commercially available so far. A large number of in vitro and in vivo investigations are necessary in order to obtain in-depth exploration about the efficiency of functional implant surfaces. The prospective titanium implants should possess the optimum chemistry, bionic characteristics, and standardized modern topographies to achieve rapid osseointegration. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Figure 1

15 pages, 1889 KiB

Open AccessReview

Modulating Tumor Cell Functions by Tunable Nanopatterned Ligand Presentation

by Katharina Amschler and Michael P. Schön

Nanomaterials 2020, 10(2), 212; https://doi.org/10.3390/nano10020212 - 26 Jan 2020

Cited by 1 | Viewed by 2889

Abstract

Cancer comprises a large group of complex diseases which arise from the misrouted interplay of mutated cells with other cells and the extracellular matrix. The extracellular matrix is a highly dynamic structure providing biochemical and biophysical cues that regulate tumor cell behavior. While [...] Read more.

Cancer comprises a large group of complex diseases which arise from the misrouted interplay of mutated cells with other cells and the extracellular matrix. The extracellular matrix is a highly dynamic structure providing biochemical and biophysical cues that regulate tumor cell behavior. While the relevance of biochemical signals has been appreciated, the complex input of biophysical properties like the variation of ligand density and distribution is a relatively new field in cancer research. Nanotechnology has become a very promising tool to mimic the physiological dimension of biophysical signals and their positive (i.e., growth-promoting) and negative (i.e., anti-tumoral or cytotoxic) effects on cellular functions. Here, we review tumor-associated cellular functions such as proliferation, epithelial-mesenchymal transition (EMT), invasion, and phenotype switch that are regulated by biophysical parameters such as ligand density or substrate elasticity. We also address the question of how such factors exert inhibitory or even toxic effects upon tumor cells. We describe three principles of nanostructured model systems based on block copolymer nanolithography, electron beam lithography, and DNA origami that have contributed to our understanding of how biophysical signals direct cancer cell fate. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Figure 1

33 pages, 907 KiB

Open AccessReview

Nanomaterials in Plants: A Review of Hazard and Applications in the Agri-Food Sector

by Eva Kranjc and Damjana Drobne

Nanomaterials 2019, 9(8), 1094; https://doi.org/10.3390/nano9081094 - 30 Jul 2019

Cited by 49 | Viewed by 4766

Abstract

Agricultural food crop plants interact with engineered nanomaterials (ENMs) from the application of agri-food nanotechnologies and from unintentional emissions originating from other nanotechnologies. Both types of exposure present implications for agricultural yield and quality, food chain transfer, and environmental and human health. In [...] Read more.

Agricultural food crop plants interact with engineered nanomaterials (ENMs) from the application of agri-food nanotechnologies and from unintentional emissions originating from other nanotechnologies. Both types of exposure present implications for agricultural yield and quality, food chain transfer, and environmental and human health. In this review, the most recent findings from agricultural plant-ENM studies published in 2017 and 2018 are summarized. The aim of this is to identify the current hazard potential of ENMs for plants grown under typical field conditions that originate from both intentional and unintentional exposures and to contribute to knowledge-based decisions on the application of ENMs in food-agriculture. We also address recent knowledge on ENM adsorption, internalization, translocation, and bioaccumulation by plants, ENM impacts on agricultural crop yield and nutrition, and ENM biotransformation. Using adverse effect level concentrations and data on ENM accumulation in environmental matrices, the literature analyses revealed that C-, Ag-, Ce-, and Ti-based ENMs are unlikely to pose a risk to plants grown under typical field conditions, whereas Cu- and Zn-based ENMs require surveillance. Since multiple factors (e.g., ENM concentration, route of exposure, and plant type) influence the effects of ENMs on plants, biomonitoring is recommended for tracking ENM environmental exposure in the future. Full article

(This article belongs to the Special Issue Non-cytotoxic Nanoparticles)

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Non-cytotoxic Nanoparticles

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (17 papers)

Editorial

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI