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3 pages, 197 KiB

Open AccessEditorial

Novel Nanomaterials for Catalytic and Biological Applications

by Mohammed Rafi Shaik, Syed Farooq Adil and Mujeeb Khan

Crystals 2023, 13(3), 427; https://doi.org/10.3390/cryst13030427 - 1 Mar 2023

Viewed by 1146

Abstract

Currently, nanotechnology has become an integral part of science and technology and has played a crucial role in the development of a variety of technological advancements in different industries [...] Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

Research

Jump to: Editorial, Review, Other

17 pages, 3381 KiB

Open AccessArticle

Green Biosynthesis of Silver Nanoparticles Using Vaccinium oxycoccos (Cranberry) Extract and Evaluation of Their Biomedical Potential

by Humaira Rizwana, Mujeeb Khan, Horiah A. Aldehaish, Syed Farooq Adil, Mohammed Rafi Shaik, Mohamed E. Assal, Mohammad Rafe Hatshan and Mohammed Rafiq H. Siddiqui

Crystals 2023, 13(2), 294; https://doi.org/10.3390/cryst13020294 - 9 Feb 2023

Cited by 5 | Viewed by 2519

Abstract

Eco-friendly preparation of metallic nanoparticles (NPs) is a greatly evolving field of scientific research. These types of NPs have gained substantial recognition from scientists, including chemists, chemical biologists and technologists, who have successfully exploited them for the fabrication of a variety of advanced [...] Read more.

Eco-friendly preparation of metallic nanoparticles (NPs) is a greatly evolving field of scientific research. These types of NPs have gained substantial recognition from scientists, including chemists, chemical biologists and technologists, who have successfully exploited them for the fabrication of a variety of advanced nanodevices. Herein, silver (Ag) NPs were synthesized by a green approach using the aqueous extract of Vaccinium oxycoccos (cranberry), which not only reduced the silver ions but also stabilized the surface of the resultant Ag NPs. The formation of Ag NPs is confirmed by different analytical techniques, including powder X-ray diffraction, UV analysis, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FT-IR). The UV analysis of the aqueous solution of the reaction mixture demonstrated an absorption band at ~450 nm, which is the typical peak of Ag NPs, leading to the confirmation of product formation. While the XRD confirmed the crystallinity of the sample and the formation of a face-centered cubic (fcc) structure, on the other hand, TEM revealed the presence of spherical NPs with an approximate size range between 5–30 nm. Furthermore, the as-obtained Ag NPs were subjected to thorough investigations to explore the biomedical potential of the sample. In this case, the Ag NPs demonstrated considerable antioxidant and antifungal properties towards various pathogens. In addition, Ag NPs also showed substantial inhibition of spore germination. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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19 pages, 5320 KiB

Open AccessArticle

Lyotropic Liquid Crystal System for Drug Delivery of Astaxanthin: Physical Characterization and Enhanced Antioxidant Potential

by Sapna Kumari, Anju Goyal, Madhukar Garg, Angela Antonescu and Rakesh K. Sindhu

Crystals 2023, 13(1), 142; https://doi.org/10.3390/cryst13010142 - 13 Jan 2023

Cited by 8 | Viewed by 2692

Abstract

Astaxanthin is a xanthophyll carotenoid, well known for its potent anti-inflammatory and antioxidant properties, owing to its unsaturated molecular structure. Aquatic plants and animals contain the hydrophobic carotenoid astaxanthin, which is thought to possess a number of advantageous biological traits. However, due to [...] Read more.

Astaxanthin is a xanthophyll carotenoid, well known for its potent anti-inflammatory and antioxidant properties, owing to its unsaturated molecular structure. Aquatic plants and animals contain the hydrophobic carotenoid astaxanthin, which is thought to possess a number of advantageous biological traits. However, due to its weak bioavailability and low water solubility, its use as a nutraceutical in food is currently restricted. Cubosomal encapsulation has been considered an effective alternative for improving the bioavailability and solubility of hydrophobic bioactives. The current paper aimed to conquer these issues by encapsulating astaxanthin in lyotropic liquid crystal nano-formulations prepared via the fabrication method. The physicochemical properties of astaxanthin-loaded cubosomes (AST-LC) have also been analyzed, in order to know the morphology of the prepared formulations and their bioavailability in the biological system. The formulation has been tested for particle size, thermal behavior, zeta potential, crystallinity, encapsulation efficiency, and drug-polymer interactions. The observed experimental results showed the particle size and zeta potential of astaxanthin-loaded cubosomes (AST-LC) as 199 ± 0.23 nm −27.4 ± 4.67 mV, with a small polydispersity index (0.283 ± 1.01). The cubic structure and nano-range size of the ideal formulation were verified by a field emission scanning electron microscope (FESEM) and (HRTEM) high-resolution transmission electron microscopic examination. The formulation exhibits a higher encapsulation efficiency with good yield. Results from X-ray diffraction and diffraction scanning calorimetry demonstrated an amorphous state of astaxanthin incorporated into the formulation. Fourier transform infrared spectroscopy (FTIR) analysis of AST-LC showed the absence of astaxanthin main peaks, indicating its complete encapsulation inside the formulation. The drug–excipient interaction was carried out with diffraction scanning calorimetry DSC and FTIR, resulting in no interaction between them. These results offered important details about increasing astaxanthin bioavailability by incorporating it into cubosomes. Furthermore, the astaxanthin loaded into cubosomes has been evaluated for antioxidant potency, compared with astaxanthin extract using 2,2-diphenylpicrylhydrazylassay (DPPH assay). Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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14 pages, 2730 KiB

Open AccessArticle

Diagnosis and Control of Brown Leaf Spot of Kiwi (Actinidia deliciosa) Using Biochar-Zinc Oxide Nanocomposite (MB-ZnO) as a Non-Toxic Bio-Fungicides

by Asif Kamal, Musrat Ali, Dunia A. Al Farraj, Enshad M. Al-Zaidi, Maria Khizar, Reem Amer Aljaaidi, Mohmed S. Elshikh and Muhammad Farooq Hussain Munis

Crystals 2023, 13(1), 98; https://doi.org/10.3390/cryst13010098 - 5 Jan 2023

Cited by 2 | Viewed by 2402

Abstract

Kiwi is one of the best natural sources of vitamin C and has wide applications. During October–November 2021, small brown spots were examined on the Kiwi leaves. The diseased leaf samples were collected and placed on potato dextrose agar nutrient media for diagnosis. [...] Read more.

Kiwi is one of the best natural sources of vitamin C and has wide applications. During October–November 2021, small brown spots were examined on the Kiwi leaves. The diseased leaf samples were collected and placed on potato dextrose agar nutrient media for diagnosis. Morphological, anatomical, and molecular studies revealed this disease-causing agent to be Rhizopus oryzae. Molecular characterizations of the isolated pathogen were performed by using actin translation elongation factor (EF-1α) and ribosomal deoxyribose nucleotide inter transcribed sequence (rDNA ITS ITS1/ITS4) and elongation factors (EFl-F/EFl-R) primers. A BLAST study of the resultant ITS1/ITS4 sequence showed > 99% resemblance with R. oryzae (MT603964.1), while the EF-1α sequence revealed 100% similarity with translation elongation factor-1α gene of R. oryzae (MK510718.1). The obtained ITS1/ITS4 sequence was submitted to NCBI (MW603842.1). Koch’s postulates established the pathogenicity of isolated R. oryzae and proved it to be the brown spot pathogen of Kiwi. For the environmentally-friendly management of Kiwi leaf spot, maize biochar-Zinc Oxide (MB-ZnO) nanocomposite was used. The prepared nanocomposite was characterized by Fourier transform infrared (FTIR) spectroscopy, thermo gravitational analysis (TGA), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis. After successful preparation, MB-ZnO was assessed for its possible antifungal potential against R. oryzae. MB-ZnO displayed substantial growth inhibition, and the highest growth inhibition (79%) was observed at a 19 mg/mL dose rate of nanoparticles. These excellent findings propose that Ball-milled synthesis is a fast, economical, and environmentally friendly method for nanocomposite in the near future. The nanocomposite is used as a nominal substitute for chemical fungicides. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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12 pages, 3460 KiB

Open AccessArticle

Layer-by-Layer Extracellular Biological Synthesis of Sustainable Ag-Based Nanoparticles for Catalytic Reduction of Methylene Blue Dye

by Mohamed G. M. Kordy, Inas A. Ahmed, Mohammed Abdel-Gabbar, Hanan A. Soliman, Abeer S. Altowyan and Mohamed Shaban

Crystals 2022, 12(11), 1576; https://doi.org/10.3390/cryst12111576 - 4 Nov 2022

Cited by 6 | Viewed by 1780

Abstract

Novel cubic microstructures for the purposes of plasmonic Ag-based NPs were made using biological wastes produced from a microbial culture of Bacillus cereus (B. cereus) employing a bottom-up approach for the biosynthesis of metal-based nanomaterials. The unique surface plasmon resonance (SPR) [...] Read more.

Novel cubic microstructures for the purposes of plasmonic Ag-based NPs were made using biological wastes produced from a microbial culture of Bacillus cereus (B. cereus) employing a bottom-up approach for the biosynthesis of metal-based nanomaterials. The unique surface plasmon resonance (SPR) of the as-prepared Ag-based NPs was detected at 405 nm. The infra-red spectrum revealed that the used biological waste effectively stabilized our Ag-based NPs. Scanning and transmission electron microscopes were used in order to evaluate the sizes and shapes of the distinctive structures present in our samples. The Ag NPs had a face-centered cubic structure, with a size of 64.4 nm for the (200) nano-crystallites, according to the X-ray diffraction that was conducted. The zeta potential was found to be −19.5 mV and the dynamic light scattering (DLS) size was 238.8 nm. Methylene blue’s (MB) reaction with NaBH₄ was used in order to measure the catalytic activity of the generated Ag-based NPs over a period of 1 to 5 min. With an astonishing reaction rate of 0.2861 min⁻¹, the MB elimination percentage reached 67% in just 5 min, displaying outstanding catalytic activity. This work can therefore encourage the use of this biowaste for the ecologically benign, cost-effective, and long-term synthesis of innovative Ag-based nanoparticles and nanostructures, as well as in their use as catalysts in the catalytic reduction in MB. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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20 pages, 4290 KiB

Open AccessArticle

Nanocrystal-Based Topical Gels for Improving Wound Healing Efficacy of Curcumin

by Vinith Kotian, Marina Koland and Srinivas Mutalik

Crystals 2022, 12(11), 1565; https://doi.org/10.3390/cryst12111565 - 3 Nov 2022

Cited by 8 | Viewed by 2547

Abstract

Topical curcumin shows poor local availability because of its low aqueous solubility and inadequate tissue absorption. Curcumin nanocrystals were prepared by sonoprecipitation followed by lyophilization to improve surface area and solubility. The formulation was optimized by the Design of Experiment (DoE) approach. The [...] Read more.

Topical curcumin shows poor local availability because of its low aqueous solubility and inadequate tissue absorption. Curcumin nanocrystals were prepared by sonoprecipitation followed by lyophilization to improve surface area and solubility. The formulation was optimized by the Design of Experiment (DoE) approach. The nanocrystals were characterized for particle size, zeta potential, polydispersity index, scanning electron microscopy (SEM), powder x-ray diffraction (PXRD), practical yield and in vitro drug release studies. The nanocrystal-incorporated gel was evaluated for drug content, ex vivo permeation, in vivo skin irritation, and in vivo wound healing activity. Time of sonication and amplitude influenced the optimization of curcumin nanocrystals, but the effect of stabilizer concentrations was not significant beyond 0.5% w/w. SEM images of curcumin nanocrystals revealed irregular and plate-shaped particles with rough surfaces. PXRD patterns of curcumin nanocrystals showed low crystallinity compared to unprocessed curcumin powder. An in vitro drug release study demonstrated significant improvement in the percentage cumulative drug release in the form of nanocrystals compared to the unprocessed curcumin, and the release profile exhibited first-order kinetics. Curcumin nanocrystal gel showed 93.86% drug content and was free of skin irritation potential. Excision wound healing activity in albino rats showed that the curcumin nanocrystal gel exhibited significantly faster wound contraction than curcumin powder-incorporated gel. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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13 pages, 3287 KiB

Open AccessArticle

Green Synthesis of Chitosan Nanoparticles Using of Martynia annua L. Ethanol Leaf Extract and Their Antibacterial Activity

by Narayanasamy Duraisamy, Sangeetha Dhayalan, Mohammed Rafi Shaik, Althaf Hussain Shaik, Jilani P. Shaik and Baji Shaik

Crystals 2022, 12(11), 1550; https://doi.org/10.3390/cryst12111550 - 30 Oct 2022

Cited by 11 | Viewed by 3545

Abstract

The herbal-based drug isolation-related research has increased recently around the globe. Accordingly, the current study was designed to evaluate the phytochemical content of ethanol extract of Martynia annua and its chitosan nanoparticles (MA-CNPs) antibacterial activity against bacterial pathogens such as Bacteroides fragilis, [...] Read more.

The herbal-based drug isolation-related research has increased recently around the globe. Accordingly, the current study was designed to evaluate the phytochemical content of ethanol extract of Martynia annua and its chitosan nanoparticles (MA-CNPs) antibacterial activity against bacterial pathogens such as Bacteroides fragilis, Streptococcus oralis MTCC 2696, Propionibacterium acnes MTCC 1951, Pseudomonas aeruginosa MTCC 424, Staphylococcus aureus MTCC 2940, E. coli MTCC 443, Bacillus cereus MTCC 441, Streptococcus mutans MTCC 890, Aeromonas hydrophila MTCC 12301, and Streptococcus faecalis by agar well diffusion methods. The obtained results showed that the ethanol extract of M. annua contains more pharmaceutically valuable phytochemicals than other solvent extracts and its mediated chitosan nanoparticles showed effective antibacterial activities. The ethanol extract also effectively reduced, capped, and stabilized the chitosan into MA-CNPs. The green synthesized MA-CNPs were characterized and confirmed through UV-visible spectrophotometer, FT-IR, SEM, and DLS analyses. The MA-CNPs exhibited considerable antibacterial activity in the order of Bacteroides fragilis > Streptococcus oralis > Propionibacterium acnes > Pseudomonas aeruginosa > Staphylococcus aureus > E. coli > Bacillus cereus > Streptococcus mutans > Aeromonas hydrophila> Streptococcus faecalis. Finally, the results strongly recommended that the ethanol extract of M. annua-mediated chitosan nanoparticles could be considered an effective nanomaterial to control microbial pathogens. Further, therapeutical uses of MA-CNPs need in vitro and in vivo investigation. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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16 pages, 4530 KiB

Open AccessArticle

Evaluation of Antioxidant, Cytotoxic, Mutagenic and Other Inhibitory Potentials of Green Synthesized Chitosan Nanoparticles

by Narayanasamy Duraisamy, Sangeetha Dhayalan, Mohammed Rafi Shaik, Althaf Hussain Shaik, Jilani P. Shaik and Baji Shaik

Crystals 2022, 12(11), 1540; https://doi.org/10.3390/cryst12111540 - 28 Oct 2022

Cited by 3 | Viewed by 1703

Abstract

The current study was performed with aim of evaluating antioxidant, cytotoxicity, α-amylase, and α-glucosidase inhibitory activities and mutagenicity properties of Martynia annua mediated Chitosan nanoparticles (MAL-CNPs). The green synthesized MAL-CNPs were characterized and confirmed through several characterization techniques, including UV-visible spectroscopy (UV-Vis), high-resolution [...] Read more.

The current study was performed with aim of evaluating antioxidant, cytotoxicity, α-amylase, and α-glucosidase inhibitory activities and mutagenicity properties of Martynia annua mediated Chitosan nanoparticles (MAL-CNPs). The green synthesized MAL-CNPs were characterized and confirmed through several characterization techniques, including UV-visible spectroscopy (UV-Vis), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and dynamic light scattering (DLS). The HR-TEM analysis exhibited that the as-synthesized chitosan nanoparticles are spherical in shape. Furthermore, the DLS analysis exhibited that the average size of MAL-CNPs was 53 nm and the maximum diameter was 130.7 nm. The antioxidant activity results revealed that the MAL-CNPs showed DPPH (2,2-diphenyl-1-picrylhydrazyl) (66.78%) and H₂O₂ (91.65%) scavenging activities at 50 µg/mL concentration. The IC₅₀ values were 2.431 μg/mL and 50 µg/mL for DPPH and H₂O₂, respectively. MTT (3-4, 5 dimethylthiazol-2yl-2, 5-diphenyltetrazolium bromide) assay results exhibited dose-dependent cytotoxicity found from 50 μg/mL concentration of MAL-CNPs. The MAL-CNPs showed remarkable α-glucosidase and α-amylase inhibitory activity (IC₅₀ 1.981 μg/mL and 161.8 μg/mL). No toxic effect of MAL-CNPs was found through the Ames test. Further, the study concluded that MAL-CNPs are non-toxic and possess adequate antioxidants and cytotoxicity activity against cancer cells, α-glucosidase, and α-amylase inhibitory activity. Hence, the MAL-CNPs were considered for biomedical applications after the assessment of their efficiency and safety. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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20 pages, 3154 KiB

Open AccessArticle

Green Synthesis of Zinc Oxide Nanocrystals Utilizing Origanum majorana Leaf Extract and Their Synergistic Patterns with Colistin against Multidrug-Resistant Bacterial Strains

by Mohamed Taha Yassin, Abdulaziz Abdulrahman Al-Askar, Khalid Maniah and Fatimah O. Al-Otibi

Crystals 2022, 12(11), 1513; https://doi.org/10.3390/cryst12111513 - 25 Oct 2022

Cited by 20 | Viewed by 5469

Abstract

There is a crucial necessity for the formulation of efficient antimicrobial agents owing to the increasing prevalence of hospital-acquired bacterial infections triggered by multidrug-resistant microbes that result in significant deaths and illnesses around the world. Hence, the current investigation examined the antibacterial proficiency [...] Read more.

There is a crucial necessity for the formulation of efficient antimicrobial agents owing to the increasing prevalence of hospital-acquired bacterial infections triggered by multidrug-resistant microbes that result in significant deaths and illnesses around the world. Hence, the current investigation examined the antibacterial proficiency of zinc oxide nanoparticles formulated utilizing the green route against bacterial strains that were resistant to multiple drugs. In addition, the synergistic antibacterial action of ZnO nanoparticles (ZnO NPs) combined with colistin was investigated against the tested microbial strains to determine the efficiency of the bioinspired ZnO nanoparticles in boosting the antibacterial proficiency of colistin antibiotic. Incidentally, the bioinspired ZnO nanoparticles were synthesized using water extract of Origanum majorana leaves and these nanomaterials were physicochemically characterized using different analytical techniques. The bioactivity of the synthesized nanomaterials against multidrug-resistant bacterial strains was appraised using the agar diffusion method. The biogenic ZnO NPs at a concentration of 100 μg/disk revealed a compelling antimicrobial efficacy against the tested strains, expressing the maximum antimicrobial action against Escherichia coli strain with clear zone diameter of 38.16 ± 0.18 mm. The remarkable antibacterial proficiency might be accredited to the tiny particle size of the bioformulated ZnO NPs of 12.467 ± 1.36 nm. The net charge of ZnO nanomaterials was −14.8 mV while XRD analysis confirmed their hexagonal wurtzite structure. Furthermore, the bioformulated ZnO NPs showed a promising synergistic potency with colistin demonstrating respective synergism proportions of 91.05, 79.07, 75.04, 75.25, 56.28 and 10.60% against E. coli, Klebsiella pneumoniae, Acinetobacter baumannii, Salmonella typhimurium, Enterobacter cloacae, and Pseudomonas aeruginosa, respectively. In conclusion, the water extract of O. majorana leaves mediated green formulation of zinc oxide nanoparticles with unique physicochemical characteristics and effective antibacterial proficiency against the examined drug-resistant bacterial strains. These nanomaterials could be used in the synthesis of effective antibacterial coatings to control hospital acquired infections caused by multidrug-resistant bacterial pathogens. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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16 pages, 6833 KiB

Open AccessArticle

Biogenic Synthesis of Zero Valent Fe/Magnetite Fe₃O₄ Nanoparticles Using Caralluma acutangula and Application for Methylene Blue Dye Degradation under UV Light Irradiation

by Waleed M. Alamier, Medhat Mohamed El-Moselhy, Ayyob M. Bakry, Nazim Hasan and Abdullah Ali Alamri

Crystals 2022, 12(11), 1510; https://doi.org/10.3390/cryst12111510 - 25 Oct 2022

Cited by 5 | Viewed by 1977

Abstract

Biogenic synthesis of nanoparticles using plant extract is a promising trend in research to reduce chemical consumption and avoid wastewater treatment complications. In this work, the zero-valent Fe/Fe₃O₄ nanoparticles (Fe⁰/Fe₃O₄ NPs) were synthesized using Caralluma [...] Read more.

Biogenic synthesis of nanoparticles using plant extract is a promising trend in research to reduce chemical consumption and avoid wastewater treatment complications. In this work, the zero-valent Fe/Fe₃O₄ nanoparticles (Fe⁰/Fe₃O₄ NPs) were synthesized using Caralluma acutangula (CA) plant, widespread in the Jazan region in Saudi Arabia. The synthesis process involves hydrothermal treatment of plant extract and iron (III) mixture at 80 °C to facilitate the reduction reaction of iron (III) cations. The Fe⁰/Fe₃O₄ NPs were characterized by XRD, FTIR, SEM, EDX, TEM, XPS, TGA, UV, and S_BET. The obtained data support the formation of Fe⁰/Fe₃O₄ NPs crystal structure with an average particle size of 9.6 nm and surface area of 89 m².g⁻¹. The biosynthesized Fe⁰/Fe₃O₄ NPs were then applied for the photodegradation of Methylene blue (MB) dye as one of the most common organic dyes in wastewater due to several industrial human activities. Different parameters for MB degradation were performed, such as kinetics and thermodynamics studies. The data obtained reflect the nonspontaneous endothermic process with 87.8 KJ. mol⁻¹ activation energy (E_a). Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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14 pages, 4653 KiB

Open AccessArticle

Green Synthesized Cu₂O-Cu(OH)₂@Cu Nanocomposites with Fenton-like Catalytic Properties for the Degradation of Cationic and Anionic Dyes

by Hala A. Al-Jawhari and Nuha A. Alhebshi

Crystals 2022, 12(10), 1328; https://doi.org/10.3390/cryst12101328 - 20 Sep 2022

Viewed by 1977

Abstract

In this work, we introduce an environmental and sustainable approach to grow free standing heterogeneous Cu₂O-Cu(OH)₂ nanocomposites on a Cu mesh using spinach leaf extract and glycerol. Structural characterizations for samples annealed at 200 °C revealed that there is more [...] Read more.

In this work, we introduce an environmental and sustainable approach to grow free standing heterogeneous Cu₂O-Cu(OH)₂ nanocomposites on a Cu mesh using spinach leaf extract and glycerol. Structural characterizations for samples annealed at 200 °C revealed that there is more Cu(OH)₂ than Cu₂O on the mesh surface. The photocatalytic activity of the green synthesized catalyst was studied for degradation of a cationic dye methylene blue (MB), an anionic dye methyl orange (MO) and a mixture of both dyes. The effect of changing the dye’s initial pH value on the photodegradation process was explored. After 40 min of irradiation under sunlight, with a maximum intensity of 5 mW/cm², a basic MB dye (pH-11) showed about 80% color removal with an average kinetic rate of 94.5 m·min⁻¹. In contrast, 93% of the acidified MO dye (pH-2) was degraded with an average kinetic rate of 126.5 m·min⁻¹. Moreover, the versatility of the Cu₂O-Cu(OH)₂@Cu mesh was evaluated using a remarkable selective separability for a mixture of MB and MO at pH = 2, in the dark and under normal sunlight. Such promising outcomes indicate the potential of our green composites to degrade dyes as both photocatalysts under daylight and as Fenton-like catalysts in darkness. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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13 pages, 4314 KiB

Open AccessArticle

Identification of Novel AXL Kinase Inhibitors Using Ligand-Based Pharmacophore Screening and Molecular Dynamics Simulations

by Lavanya Nagamalla, J. V. Shanmukha Kumar, Mohammed Rafi Shaik, Chintakindi Sanjay, Ali M. Alsamhan, Mohsin Ahmed Kasim and Abdulrahman Alwarthan

Crystals 2022, 12(8), 1158; https://doi.org/10.3390/cryst12081158 - 17 Aug 2022

Cited by 2 | Viewed by 2175

Abstract

AXL kinase is a promising target in novel drug discovery for cancer. A ligand-based pharmacophore model was generated with the Pharmit web server. Its inbuilt PubChem molecule database was screened and led to 408 candidate molecules. Docking of the AXL kinase active sites [...] Read more.

AXL kinase is a promising target in novel drug discovery for cancer. A ligand-based pharmacophore model was generated with the Pharmit web server. Its inbuilt PubChem molecule database was screened and led to 408 candidate molecules. Docking of the AXL kinase active sites with the identified list of candidate molecules was carried out with Autodock Vina docking software. This resulted in four compounds selected for further investigation. Molecular dynamics simulation of two ligands (PubChem-122421875 and PubChem-78160848) showed considerable binding with AXL kinase. From the MM-PBSA binding free energies investigation, the PubChem-122421875 (G = −179.3 kJ/mol) and PubChem-78160848 (G = −208.3 kJ/mol) ligands had favorable protein-ligand complex stability and binding free energy. Hence, PubChem-122421875 and PubChem-78160848 molecules identified in this work could be a potent starting point for developing novel AXL kinase inhibitor molecules. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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20 pages, 4450 KiB

Open AccessArticle

Synergistic Antibacterial Activity of Green Synthesized Silver Nanomaterials with Colistin Antibiotic against Multidrug-Resistant Bacterial Pathogens

by Mohamed Taha Yassin, Ashraf Abdel-Fattah Mostafa, Abdulaziz Abdulrahman Al-Askar and Fatimah O. Al-Otibi

Crystals 2022, 12(8), 1057; https://doi.org/10.3390/cryst12081057 - 29 Jul 2022

Cited by 35 | Viewed by 4120

Abstract

The high frequency of nosocomial bacterial infections caused by multidrug-resistant pathogens contributes to significant morbidity and mortality worldwide. As a result, finding effective antibacterial agents is of critical importance. Hence, the aim of the present study was to greenly synthesize silver nanoparticles (AgNPs) [...] Read more.

The high frequency of nosocomial bacterial infections caused by multidrug-resistant pathogens contributes to significant morbidity and mortality worldwide. As a result, finding effective antibacterial agents is of critical importance. Hence, the aim of the present study was to greenly synthesize silver nanoparticles (AgNPs) utilizing Salvia officinalis aqueous leaf extract. The biogenic AgNPs were characterized utilizing different physicochemical techniques such as energy-dispersive X-ray spectroscopy (EDX), ultraviolet-visible spectrophotometry (UV-Vis), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR) analysis. Additionally, the synergistic antimicrobial effectiveness of the biosynthesized AgNPs with colistin antibiotic against multidrug-resistant bacterial strains was evaluated utilizing the standard disk diffusion assay. The bioformulated AgNPs revealed significant physicochemical features, such as a small particle size of 17.615 ± 1.24 nm and net zeta potential value of −16.2 mV. The elemental mapping of AgNPs revealed that silver was the main element, recording a relative mass percent of 83.16%, followed by carbon (9.51%), oxygen (5.80%), silicon (0.87%), and chloride (0.67%). The disc diffusion assay revealed that AgNPs showed antibacterial potency against different tested bacterial pathogens, recording the highest efficiency against the Escherichia coli strain with an inhibitory zone diameter of 37.86 ± 0.21 mm at an AgNPs concentration of 100 µg/disk. In addition, the antibacterial activity of AgNPs was significantly higher than that of colistin (p ≤ 0.05) against the multidrug resistant bacterial strain namely, Acinetobacter baumannii. The biosynthesized AgNPs revealed synergistic antibacterial activity with colistin antibiotic, demonstrating the highest synergistic percent against the A. baumannii strain (85.57%) followed by Enterobacter cloacae (53.63%), E. coli (35.76%), Klebsiella pneumoniae (35.19%), Salmonella typhimurium (33.06%), and Pseudomonas aeruginosa (13.75%). In conclusion, the biogenic AgNPs revealed unique physicochemical characteristics and significant antibacterial activities against different multidrug-resistant bacterial pathogens. Consequently, the potent synergistic effect of the AgNPs–colistin combination highlights the potential of utilizing this combination for fabrication of highly effective antibacterial coatings in intensive care units for successful control of the spread of nosocomial bacterial infections. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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13 pages, 5151 KiB

Open AccessArticle

Assessment of Physicochemical, Anticancer, Antimicrobial, and Biofilm Activities of N-Doped Graphene

by Abdulaziz Alangari, Fahad M. Aldakheel, Ayesha Mateen, Mohammed S. Alqhatani, Ahmed L. Alaofi, Mudassar Shahid, Raisuddin Ali, Rabbani Syed, Syed Farooq Adil, Mujeeb Khan, Mufsir Kuniyil and Mohammed Rafi Shaik

Crystals 2022, 12(8), 1035; https://doi.org/10.3390/cryst12081035 - 26 Jul 2022

Cited by 3 | Viewed by 2400

Abstract

Nanomedicine has been used as a precise treatment for many diseases. The advantage of using nanodrugs is that they have more permeability and less toxicity to cells, which enhances the drug delivery system. Graphene is well known for its potential biological applications in [...] Read more.

Nanomedicine has been used as a precise treatment for many diseases. The advantage of using nanodrugs is that they have more permeability and less toxicity to cells, which enhances the drug delivery system. Graphene is well known for its potential biological applications in drug, food, and pharma industries. This study aimed to assess the productivity and potentiality of nitrogen-doped graphene (NDG) and to evaluate their anticancer, antimicrobial, and biofilm inhibition activity. Nitrogen-doped graphene was synthesized by using a one-pot facile synthesis of NDG, wherein the NDG was prepared by the reduction of graphene oxide (GO) in the presence of hydrazine hydrate as a reducing agent, while ammonium hydroxide was used as a source of nitrogen on the surface of graphene. As-synthesized NDG was characterized by various characterization techniques such as UV-Vis, FT-IR, XRD, XPS, TEM, and N₂ sorption studies analysis. Antimicrobial, anticancer, and biofilm inhibition assays were performed by standard protocols. N-doped graphene (NDG) showed better activity against Gram-positive bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), Bacillus subtillis, Streptococcus pneumoniae, and Streptococcus mutans (p ≤ 0.05), whereas there was no activity against Gram-negative strains in Klebsiella pneumoniae and Pseudomonas aeruginosa. Biofilm inhibition was also improved with NDG compared to the standard ampicillin. NDG showed better results in both MCF-7 and Hela cell lines with IC₅₀ of 27.15 µg/mL and 30.85 µg/mL, respectively. In conclusion, NDG has the best ability for use as a biomolecule, and research studies focusing on proteomics, metabolomics, and in vivo studies are needed to increase the impact of NDG in the drug and pharma industry. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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13 pages, 3270 KiB

Open AccessArticle

The Crystal Structure of 3-Amino-1-(4-Chlorophenyl)-9-Methoxy-1H-Benzo[f]Chromene-2-Carbonitrile: Antimicrobial Activity and Docking Studies

by Rawda M. Okasha, Ahmed M. Fouda, Majed A. Bajaber, Hazem A. Ghabbour, Abd El-Galil E. Amr, Ahmed M. Naglah, Abdulrahman A. Almehizia, Ahmed A. Elhenawy and Ahmed M. El-Agrody

Crystals 2022, 12(7), 982; https://doi.org/10.3390/cryst12070982 - 14 Jul 2022

Cited by 7 | Viewed by 1752

Abstract

Compound 3-amino-1-(4-chlorophenyl)-9-methoxy-1H-benzo[f]chromene-2-carbonitrile (4), was synthesized via the reaction of 7-methoxynaphthalen-2-ol (1), 4-chlorobenzaldehyde (2), and malononitrile (3) in an ethanolic piperidine solution under microwave irradiation. The synthesized pyran derivative 4 was asserted [...] Read more.

Compound 3-amino-1-(4-chlorophenyl)-9-methoxy-1H-benzo[f]chromene-2-carbonitrile (4), was synthesized via the reaction of 7-methoxynaphthalen-2-ol (1), 4-chlorobenzaldehyde (2), and malononitrile (3) in an ethanolic piperidine solution under microwave irradiation. The synthesized pyran derivative 4 was asserted through spectral data and X-ray diffraction. The molecular structure of compound 4 was established unambiguously through the single crystal X-ray measurements and crystallized in the Triclinic, P-1, a = 8.7171 (4) Å, b = 10.9509 (5) Å, c = 19.5853 (9) Å, α = 78.249 (2)°, β = 89.000 (2)°, γ = 70.054 (2)°, V = 1717.88 (14) Å³, Z = 4. The target molecule has been screened for antibacterial and antifungal functionality. Compound 4 exhibited favorable antimicrobial activities that resembled the reference antimicrobial agents with an IZ range of 16–26 mm. In addition, MIC, MBC, and MFC were assessed and screened for molecule 4, revealing bactericidal and fungicidal effects. Lastly, a molecular docking analysis was addressed and conducted for this desired molecule. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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18 pages, 6186 KiB

Open AccessArticle

Synergistic Antifungal Efficiency of Biogenic Silver Nanoparticles with Itraconazole against Multidrug-Resistant Candidal Strains

by Mohamed Taha Yassin, Ashraf Abdel-Fattah Mostafa, Abdulaziz Abdulrahman Al-Askar and Fatimah O. Al-Otibi

Crystals 2022, 12(6), 816; https://doi.org/10.3390/cryst12060816 - 8 Jun 2022

Cited by 13 | Viewed by 3393

Abstract

Fungal infections caused by multidrug-resistant strains are considered one of the leading causes of morbidity and mortality worldwide. Moreover, antifungal medications used in conventional antifungal treatment revealed poor therapeutic effectiveness and possible side effects such as hepatotoxicity, nephrotoxicity, and myelotoxicity. Therefore, the current [...] Read more.

Fungal infections caused by multidrug-resistant strains are considered one of the leading causes of morbidity and mortality worldwide. Moreover, antifungal medications used in conventional antifungal treatment revealed poor therapeutic effectiveness and possible side effects such as hepatotoxicity, nephrotoxicity, and myelotoxicity. Therefore, the current study was developed to determine the antifungal effectiveness of green synthesized silver nanoparticles (AgNPs) and their synergistic efficiency with antifungal drugs against multidrug-resistant candidal strains. The AgNPs were greenly synthesized using the aqueous peel extract of Punica granatum. In addition, AgNPs were characterized using ultraviolet-visible spectrophotometry (UV/Vis), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction analysis (XRD), and zeta potential analysis. In this regard, UV-vis analysis indicated SPR of AgNPs at 396 nm, while the particle size distribution revealed that the average particle size was 18.567 ± 1.46 nm. The surface charge of AgNPs was found to be −15.6 mV, indicating their stability in aqueous solutions. The biofabricated AgNPs indicated antifungal activity against Candida tropicalis, C. albicans, and C. glabrata strains showing inhibitory zone diameters of 23.78 ± 0.63, 21.38 ± 0.58, and 16.53 ± 0.21 mm, respectively while their minimum inhibitory concentration (MIC) was found to be 2.5 µg/mL against C. tropicalis strain. AgNPs and itraconazole revealed the highest synergistic activity against the multidrug-resistant strain, C. glabrata, recording a synergism percentage of 74.32%. In conclusion, the biogenic AgNPs in combination with itraconazole drug exhibited potential synergistic activity against different candidal strains indicating their potential usage in the bioformulation of highly effective antifungal agents. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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20 pages, 5776 KiB

Open AccessArticle

Facile Green Synthesis of Zinc Oxide Nanoparticles with Potential Synergistic Activity with Common Antifungal Agents against Multidrug-Resistant Candidal Strains

by Mohamed Taha Yassin, Ashraf Abdel-Fattah Mostafa, Abdulaziz Abdulrahman Al-Askar and Fatimah O. Al-Otibi

Crystals 2022, 12(6), 774; https://doi.org/10.3390/cryst12060774 - 26 May 2022

Cited by 37 | Viewed by 4702

Abstract

The high incidence of fungal resistance to antifungal drugs represents a global concern, contributing to high levels of morbidity and mortality, especially among immunocompromised patients. Moreover, conventional antifungal medications have poor therapeutic outcomes, as well as possible toxicities resulting from long-term administration. Accordingly, [...] Read more.

The high incidence of fungal resistance to antifungal drugs represents a global concern, contributing to high levels of morbidity and mortality, especially among immunocompromised patients. Moreover, conventional antifungal medications have poor therapeutic outcomes, as well as possible toxicities resulting from long-term administration. Accordingly, the aim of the present study was to investigate the antifungal effectiveness of biogenic zinc oxide nanoparticles (ZnO NPs) against multidrug-resistant candidal strains. Biogenic ZnO NPs were characterized using physicochemical methods, such as UV-vis spectroscopy, transmission electron microscopy (TEM), energy-dispersive X ray (EDX) spectroscopy, FTIR (Fourier transform infrared) spectroscopy and X-ray powder diffraction (XRD) analysis. UV spectral analysis revealed the formation of two absorption peaks at 367 and 506 nm, which preliminarily indicated the successful synthesis of ZnO NPs, whereas TEM analysis showed that ZnO NPs exhibited an average particle size of 22.84 nm. The EDX spectrum confirmed the successful synthesis of ZnO nanoparticles free of impurities. The FTIR spectrum of the biosynthesized ZnO NPs showed different absorption peaks at 3427.99, 1707.86, 1621.50, 1424.16, 1325.22, 1224.67, 1178.22, 1067.69, 861.22, 752.97 and 574.11 cm⁻¹, corresponding to various functional groups. The average zeta potential value of the ZnO NPs was −7.45 mV. XRD analysis revealed the presence of six diffraction peaks at 2θ = 31.94, 34.66, 36.42, 56.42, 69.54 and 76.94°. The biogenic ZnO NPs (100 µg/disk) exhibited potent antifungal activity against C. albicans, C. glabrata and C. tropicalis strains, with suppressive zone diameters of 24.18 ± 0.32, 20.17 ± 0.56 and 26.35 ± 0.16 mm, respectively. The minimal inhibitory concentration (MIC) of ZnO NPs against C. tropicalis strain was found to be 10 μg/mL, whereas the minimal fungicidal concentration (MFC) was found to be 20 μg/mL. Moreover, ZnO NPs revealed a potential synergistic efficiency with fluconazole, nystatin and clotrimazole antifungal drugs against C. albicans strain, whereas terbinafine, nystatin and itraconazole antifungal drugs showed a potential synergism with ZnO NPs against C. glabrata as a multidrug-resistant strain. In conclusion, pomegranate peel extract mediated green synthesis of ZnO NPs with potential physicochemical features and antimicrobial activity. The biosynthesized ZnO NPs could be utilized for formulation of novel drug combinations to boost the antifungal efficiency of commonly used antifungal agents. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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17 pages, 7061 KiB

Open AccessArticle

The Crystal Structure of 2-Amino-4-(2,3-Dichlorophenyl)-6-Methoxy-4H-Benzo[h]chromene-3-Carbonitrile: Antitumor and Tyrosine Kinase Receptor Inhibition Mechanism Studies

by Ahmed M. El-Agrody, Ahmed M. Fouda, Hany M. Mohamed, Mohammed Y. Alshahrani, Hazem A. Ghabbour, Abd El-Galil E. Amr, Rawda M. Okasha, Ahmed M. Naglah, Abdulrahman A. Almehizia and Ahmed A. Elhenawy

Crystals 2022, 12(5), 737; https://doi.org/10.3390/cryst12050737 - 20 May 2022

Cited by 6 | Viewed by 2163

Abstract

The target compound, 2-amino-4-(2,3-dichlorophenyl)-6-methoxy-4H-benzo[h]chromene -3-carbonitrile (4), was synthesized via the reaction of 4-methoxynaphthalen-1-ol (1), 2,3-dichlorobenzaldehyde (2), and malononitrile (3) in an ethanolic piperidine solution under microwave irradiation. The synthesized β-enaminonitrile derivative (4) was characterized by [...] Read more.

The target compound, 2-amino-4-(2,3-dichlorophenyl)-6-methoxy-4H-benzo[h]chromene -3-carbonitrile (4), was synthesized via the reaction of 4-methoxynaphthalen-1-ol (1), 2,3-dichlorobenzaldehyde (2), and malononitrile (3) in an ethanolic piperidine solution under microwave irradiation. The synthesized β-enaminonitrile derivative (4) was characterized by spectral data and X-ray diffraction. The in vitro anti-proliferative profile was conducted against five cancer cell lines and was assessed for compound 4, which revealed strong and selective cytotoxic potency. This derivative showed promising inhibition efficacy against the EGFR and VEGFR-2 kinases in comparison to Sorafenib as a reference inhibitor. Lastly, the docking analysis into the EGFR and VEGFR-2 active sites was performed to clarify our biological findings. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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12 pages, 2206 KiB

Open AccessArticle

Cobalt, Ferrum Co-Doped Ni₃Se₄ Nano-Flake Array: An Efficient Electrocatalyst for the Alkaline Hydrogen Evolution and Overall Water Splitting

by Chuancang Zhou, Hongyu Wu, Feipeng Zhang and Yigao Miao

Crystals 2022, 12(5), 666; https://doi.org/10.3390/cryst12050666 - 5 May 2022

Cited by 7 | Viewed by 2301

Abstract

Herein, Co, Fe co-doped Ni₃Se₄ nano-flake array (Ni_0.62Co_0.35Fe_0.03)₃Se₄) was prepared on conductive carbon cloth by a two-step hydrothermal method. XRD and EDX analysis show that the nanosheets are monoclinic Ni [...] Read more.

Herein, Co, Fe co-doped Ni₃Se₄ nano-flake array (Ni_0.62Co_0.35Fe_0.03)₃Se₄) was prepared on conductive carbon cloth by a two-step hydrothermal method. XRD and EDX analysis show that the nanosheets are monoclinic Ni₃Se₄, and Co, and Fe were doped into the lattice of Ni₃Se₄. Electrochemical tests showed that Co, Fe co-doping can effectively improve the hydrogen evolution activity of Ni₃Se₄ in acidic and alkaline environment. When the current density of (Ni_0.62Co_0.35Fe_0.03)₃Se₄/CC is 10 mA/cm² in 1 M KOH solution, the overpotentials of hydrogen evolution and oxygen evolution are 87 mV and 53.9 mV, respectively, and the Tafel slopes are 122.6 and 262 mV/dec. The electrochemical active area test (ECSA) and the polarization curve test further show that (Ni_0.62Co_0.35Fe_0.03)₃Se₄/CC has a larger electrochemical active area (34.8 mF/cm²), lower electrolytic potential (0.9 V at 10 mA/cm²) and better stability. Therefore, the novel bifunctional catalyst synthesized by a simple method is a promising candidate for large-scale industrial water electrolysis. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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12 pages, 2680 KiB

Open AccessArticle

Comparative Studies of Blue-Emitting Zinc Selenide Nanocrystals Doped with Ag, Cu, and Mg towards Medical Applications

by Van Khiem Nguyen, Duy Khanh Pham, Ngoc Quyen Tran, Le Hang Dang, Ngoc Hoa Nguyen, Thanh Viet Nguyen, Thi Hiep Nguyen and Thi Bich Luong

Crystals 2022, 12(5), 625; https://doi.org/10.3390/cryst12050625 - 27 Apr 2022

Cited by 6 | Viewed by 2772

Abstract

Blue-emitting Ag⁽⁺⁾-, Cu⁽²⁺⁾-, and Mg⁽²⁺⁾-doped ZnSe nanoparticles (NPs) were successfully synthesized at 80 °C by the precipitation method by using mercaptopropionic acid (MPA) as a stabilizer. UV–visible and photoluminescence (PL) studies were applied to investigate their physicochemical [...] Read more.

Blue-emitting Ag⁽⁺⁾-, Cu⁽²⁺⁾-, and Mg⁽²⁺⁾-doped ZnSe nanoparticles (NPs) were successfully synthesized at 80 °C by the precipitation method by using mercaptopropionic acid (MPA) as a stabilizer. UV–visible and photoluminescence (PL) studies were applied to investigate their physicochemical properties. Their structural properties were confirmed by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and transmission electron microscopy (TEM). The size of the ZnSe: X-capped MPA showed a strong relationship with dopant metals. The diameters of the Mg-doped ZnSe and the Cu-doped ZnSe were 22–24 nm, while the Ag-doped ZnSe was halved, at about 13 nm. The photoluminescence was within a wavelength range of 400–550 nm. In addition, the PL intensities, as well as the photoluminescence quantum yields, were in the order of the decreasing ionic radii of the dopant metals (ZnSe:Ag < ZnSe:Mg < ZnSe:Cu). Furthermore, through the interaction with lysine, the PL intensity of the ZnSe:X was changed. Interestingly, the capacity of the ZnSe:Mg for lysine was significantly higher than that of other dopant metals. Moreover, the toxicity of the ZnSe:Mg was relatively insignificant toward the hMSCs (about 80% cell viability at 320 ppm), compared to the transition-metal dopant. Therefore, the ZnSe:Mg material could have great potential for bioapplications. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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18 pages, 3453 KiB

Open AccessArticle

Facile Green Synthesis of Silver Nanoparticles Using Aqueous Leaf Extract of Origanum majorana with Potential Bioactivity against Multidrug Resistant Bacterial Strains

by Mohamed Taha Yassin, Ashraf Abdel-Fattah Mostafa, Abdulaziz Abdulrahman Al-Askar and Fatimah O. Al-Otibi

Crystals 2022, 12(5), 603; https://doi.org/10.3390/cryst12050603 - 25 Apr 2022

Cited by 63 | Viewed by 5890

Abstract

The high prevalence of nosocomial bacterial resistance contributes to significant mortality and morbidity around the world; thus, finding novel antibacterial agents is of vital concern. Accordingly, the present study attempted to synthesize silver nanoparticles (AgNPs) using a green approach. Aqueous leaf extract of [...] Read more.

The high prevalence of nosocomial bacterial resistance contributes to significant mortality and morbidity around the world; thus, finding novel antibacterial agents is of vital concern. Accordingly, the present study attempted to synthesize silver nanoparticles (AgNPs) using a green approach. Aqueous leaf extract of Origanum majorana was used to synthesize AgNPs and the antibacterial efficiency against multidrug resistant bacterial strains was detected. Characterization of the biogenic AgNPs was performed using ultraviolet-visible spectrophotometry (UV-Vis), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR) analysis, and X-ray diffraction analysis (XRD). The disc diffusion method was used to detect the antibacterial activity of AgNPs against three nosocomial multidrug-resistant strains. Preliminary UV-Vis analysis revealed the biosynthesis of AgNPs due to peak formation at 374 nm, corresponding to the surface plasmon resonance (SPR) of biogenic AgNPs. TEM micrographs detected the synthesis of small AgNPs with an average particle size of 26.63 nm. EDX analysis revealed the presence of the following elements: oxygen (3.69%), carbon (2.93%), aluminum (1.29), silicon (2.83%), chloride (17.89%), and silver (71.37%). Furthermore, XRD analysis revealed the presence of diffraction peaks at 2 theta (θ) degrees of 38.18°, 44.36°, 64.35°, and 77.54°, assigned to the planes of silver crystals (111), (200), (220), and (311), respectively. Collectively, these findings affirm the synthesis of biogenic AgNPs with potential physicochemical characteristics. The antimicrobial efficiency of the biogenic AgNPs indicated that Klebsiella pneumoniae strain was the most susceptible strain at concentrations of 50 and 100 µg/disk, with inhibitory zones of 21.57 and 24.56 mm, respectively. The minimum inhibitory concentration (MIC) of AgNPs against Klebsiella pneumoniae strain was found to be 10 µg/mL, while the minimum bactericidal concentration (MBC) was found to be 20 µg/mL. In conclusion, aqueous leaf extract of O. majorana mediated synthesis of small sized AgNPs, with potential antimicrobial effectiveness against multidrug-resistant bacterial pathogens. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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13 pages, 3226 KiB

Open AccessArticle

Green Synthesis of Silver Nanoparticles Using Juniperus procera Extract: Their Characterization, and Biological Activity

by Merajuddin Khan, Ponmurugan Karuppiah, Hamad Z. Alkhathlan, Mufsir Kuniyil, Mujeeb Khan, Syed Farooq Adil and Mohammed Rafi Shaik

Crystals 2022, 12(3), 420; https://doi.org/10.3390/cryst12030420 - 18 Mar 2022

Cited by 34 | Viewed by 3729

Abstract

Plant extract-based green synthesis of metal nanoparticles (NPs) has become a popular approach in the field of nanotechnology. In this present investigation, silver nanoparticles were prepared by an efficient and facile approach using Juniperus procera extract as a bioreducing and stabilizing agent. The [...] Read more.

Plant extract-based green synthesis of metal nanoparticles (NPs) has become a popular approach in the field of nanotechnology. In this present investigation, silver nanoparticles were prepared by an efficient and facile approach using Juniperus procera extract as a bioreducing and stabilizing agent. The as-synthesized silver nanoparticles (JP-AgNPs) were characterized by several characterization techniques such as UV–Vis, XRD, FT-IR, HR-TEM, and EDX analysis. The XRD analysis evidently confirms that the as-synthesized Ag nanoparticles (NPs) from Juniperus procera plant extract (JP-AgNPs) are crystalline in nature. FT-IR analysis confirms that the plant extract plays a dual role as a bioreducing and capping agent, while HR-TEM revealed the spherical morphology of as-synthesized JP-AgNPs with the size of ~23 nm. Furthermore, the synthesized JP-AgNPs were evaluated for antibacterial properties against several bacterial and fungal strains such as Staphylococcus aureus (ATCC 12228), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Proteus mirabilis (ATCC 4753), Cryptococcus neoformans (ATCC 16620), and Candida albicans (ATCC 885-653). The JP-AgNPs displayed an efficient mean zone of inhibition (MZI) at 50.00 µL for bacterial associated with fungal pathogens than the plant extract. Mainly, MZI values against microbial pathogens were as follows; E. coli (17.17 ± 0.72 mm), P. mirabilis (14.80 ± 0.17 mm), and C. albicans (14.30 ± 0.60 mm), whereas JP-AgNPs showed moderate activity against P. aeruginosa (11.50 ± 0.29 mm) and C. neoformans (9.83 ± 0.44 mm). Notably, the tested JP-AgNPs have displayed almost similar antimicrobial activities with that of standard antimicrobial drugs, such as streptomycin and nystatin. The enhanced antimicrobial activity of JP-AgNPs can be ascribed to the quality of resultant NPs including, uniform size, shape, and aqueous colloidal stability of nanoparticles. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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12 pages, 3002 KiB

Open AccessArticle

Fumarate Based Metal–Organic Framework: An Effective Catalyst for the Transesterification of Used Vegetable Oil

by Mohammed Rafi Shaik, Syed Farooq Adil, Zeid A. ALOthman and Osamah M. Alduhaish

Crystals 2022, 12(2), 151; https://doi.org/10.3390/cryst12020151 - 21 Jan 2022

Cited by 29 | Viewed by 3957

Abstract

Advancement of technology for the sustainable production of biodiesel is of significant importance in fighting against rising fuel costs due to the fast depletion of fossil fuels. In this regard, the application of highly efficient MOFs (metal–organic frameworks)-based materials as acidic, basic, or [...] Read more.

Advancement of technology for the sustainable production of biodiesel is of significant importance in fighting against rising fuel costs due to the fast depletion of fossil fuels. In this regard, the application of highly efficient MOFs (metal–organic frameworks)-based materials as acidic, basic, or supported heterogeneous catalysts plays a crucial role in enhancing the efficiency of biodiesel production processes. In this report, we demonstrate the synthesis and catalytic application of Zr-fumarate-MOF (also known as MOF-801) as a heterogeneous catalyst for the transesterification reaction of used vegetable oil (UVO) for the production of biodiesel. The formation of MOF-801 and its structural stability is confirmed by a variety of characterization techniques including XRD, SEM, EDX, FT-IR, BET, and TGA analyses. The results revealed the formations of highly crystalline, cubic MOF-801 possessing thermal stability below 500 °C. The MOF-801 catalyst demonstrated moderate catalytic activity during transesterification of UVO (~60%) at 50 wt.% of methanol: oil, 10 wt.% catalyst loading, 180 °C reaction temperature, and 8 h of reaction time. Furthermore, the catalyst has exhibited adequate reusability with a slight reduction in the reaction yield of up to ~10% after three cycles. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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16 pages, 34650 KiB

Open AccessArticle

Photocatalytic Degradation of Methylene Blue and Metanil Yellow Dyes Using Green Synthesized Zinc Oxide (ZnO) Nanocrystals

by S. Shwetha Priyadharshini, Jayachamarajapura Pranesh Shubha, Jaydev Shivalingappa, Syed Farooq Adil, Mufsir Kuniyil, Mohammad Rafe Hatshan, Baji Shaik and Kiran Kavalli

Crystals 2022, 12(1), 22; https://doi.org/10.3390/cryst12010022 - 24 Dec 2021

Cited by 36 | Viewed by 5090

Abstract

In this work, ZnO nanocrystals (NCs) have been effectively synthesized by a simple, efficient and cost-effective method using coconut husk extract as a novel fuel. The synthesized NCs are characterized by UV-Vis, XRD, FT-IR, SEM, EDX, Raman and PL studies. The obtained ZnO [...] Read more.

In this work, ZnO nanocrystals (NCs) have been effectively synthesized by a simple, efficient and cost-effective method using coconut husk extract as a novel fuel. The synthesized NCs are characterized by UV-Vis, XRD, FT-IR, SEM, EDX, Raman and PL studies. The obtained ZnO were found to be UV-active with a bandgap of 2.93 eV. The X-ray diffraction pattern confirms the crystallinity of the ZnO with hexagonally structured ZnO with a crystallite size of 48 nm, while the SEM analysis reveals the hexagonal bipyramid morphology. Photocatalytic activities of the synthesized ZnO NCs are used to degrade methylene blue and metanil yellow dyes. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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Review

Jump to: Editorial, Research, Other

26 pages, 998 KiB

Open AccessReview

Nano- and Crystal Engineering Approaches in the Development of Therapeutic Agents for Neoplastic Diseases

by Emmanuel M. Kiyonga, Linda N. Kekani, Tinotenda V. Chidziwa, Kudzai D. Kahwenga, Elmien Bronkhorst, Marnus Milne, Madan S. Poka, Shoeshoe Mokhele, Patrick H. Demana and Bwalya A. Witika

Crystals 2022, 12(7), 926; https://doi.org/10.3390/cryst12070926 - 29 Jun 2022

Cited by 5 | Viewed by 3209

Abstract

Cancer is a leading cause of death worldwide. It is a global quandary that requires the administration of many different active pharmaceutical ingredients (APIs) with different characteristics. As is the case with many APIs, cancer treatments exhibit poor aqueous solubility which can lead [...] Read more.

Cancer is a leading cause of death worldwide. It is a global quandary that requires the administration of many different active pharmaceutical ingredients (APIs) with different characteristics. As is the case with many APIs, cancer treatments exhibit poor aqueous solubility which can lead to low drug absorption, increased doses, and subsequently poor bioavailability and the occurrence of more adverse events. Several strategies have been envisaged to overcome this drawback, specifically for the treatment of neoplastic diseases. These include crystal engineering, in which new crystal structures are formed to improve drug physicochemical properties, and/or nanoengineering in which the reduction in particle size of the pristine crystal results in much improved physicochemical properties. Co-crystals, which are supramolecular complexes that comprise of an API and a co-crystal former (CCF) held together by non-covalent interactions in crystal lattice, have been developed to improve the performance of some anti-cancer drugs. Similarly, nanosizing through the formation of nanocrystals and, in some cases, the use of both crystal and nanoengineering to obtain nano co-crystals (NCC) have been used to increase the solubility as well as overall performance of many anticancer drugs. The formulation process of both micron and sub-micron crystalline formulations for the treatment of cancers makes use of relatively simple techniques and minimal amounts of excipients aside from stabilizers and co-formers. The flexibility of these crystalline formulations with regards to routes of administration and ability to target neoplastic tissue makes them ideal strategies for effectiveness of cancer treatments. In this review, we describe the use of crystalline formulations for the treatment of various neoplastic diseases. In addition, this review attempts to highlight the gaps in the current translation of these potential treatments into authorized medicines for use in clinical practice. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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Other

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8 pages, 1056 KiB

Open AccessOpinion

Sulfur Line Vacancies in MoS₂ for Catalytic Hydrogen Evolution Reaction

by Meng Tang, Weinan Yin, Shijie Liu, Haoxuan Yu, Yuhao He, Yuntao Cai and Longlu Wang

Crystals 2022, 12(9), 1218; https://doi.org/10.3390/cryst12091218 - 29 Aug 2022

Cited by 13 | Viewed by 2937

Abstract

Defects in transition metal dichalcogenides play important roles in the field of the catalytic hydrogen evolution reaction (HER). However, the use of defective MoS₂ as HER catalysts remains controversial because the types of defects are various, including zero-dimensional point defects, one-dimensional linear [...] Read more.

Defects in transition metal dichalcogenides play important roles in the field of the catalytic hydrogen evolution reaction (HER). However, the use of defective MoS₂ as HER catalysts remains controversial because the types of defects are various, including zero-dimensional point defects, one-dimensional linear defects, and two-dimensional plane defects. Recently, novel structures of linear defects have drawn more and more attention, and it is necessary to explore their unique properties. This review focuses on the formation mechanism, fabrication method, accurate atomic structure, and catalytic hydrogen evolution mechanism of sulfur line vacancies in MoS₂ as electrocatalysts. The structure–activity relationship between line defects and catalytic performance is discussed in detail. This will provide a route for the design of excellent catalysts by engineering line defects. Full article

(This article belongs to the Special Issue Novel Nanomaterials for Catalytic and Biological Applications)

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