A new strategy to integrate silver nanowires with waterborne coating to improve their antimicrobial and antiviral properties

Hindering the biofilm of microbial pathogens and cancer cell lines development using silver nanoparticles synthesized by epidermal mucus proteins from Clarias gariepinus

Scientists know very little about the mechanisms underlying fish skin mucus, despite the fact that it is a component of the immune system. Fish skin mucus is an important component of defence against invasive infections. Recently, Fish skin and its mucus are gaining interest among immunologists. Characterization was done on the obtained silver nanoparticles Ag combined with Clarias gariepinus catfish epidermal mucus proteins (EMP-Ag-NPs) through UV-vis, FTIR, XRD, TEM, and SEM. Ag-NPs ranged in size from 4 to 20 nm, spherical in form and the angles were 38.10°, 44.20°, 64.40°, and 77.20°, Where wavelength change after formation of EMP-Ag-NPs as indicate of dark brown, the broad band recorded at wavelength at 391 nm. Additionally, the antimicrobial, antibiofilm and anticancer activities of EMP-Ag-NPs was assessed. The present results demonstrate high activity against unicellular fungi C. albicans, followed by E. faecalis. Antibiofilm results showed strong activity against both S. aureus and P. aeruginosa pathogens in a dose-dependent manner, without affecting planktonic cell growth. Also, cytotoxicity effect was investigated against normal cells (Vero), breast cancer cells (Mcf7) and hepatic carcinoma (HepG2) cell lines at concentrations (200-6.25 µg/mL) and current results showed highly anticancer effect of Ag-NPs at concentrations 100, 5 and 25 µg/mL exhibited rounding, shrinkage, deformation and granulation of Mcf7 and HepG2 with IC50 19.34 and 31.16 µg/mL respectively while Vero cells appeared rounded at concentration 50 µg/mL and normal shape at concentration 25, 12.5 and 6.25 µg/ml with IC50 35.85 µg/mL. This study evidence the potential efficacy of biologically generated Ag-NPs as a substitute medicinal agent against harmful microorganisms. Furthermore, it highlights their inhibitory effect on cancer cell lines.

A mini review on green nanotechnology and its development in biological effects

The utilization of living organisms for the creation of inorganic nanoscale particles is a potential new development in the realm of biotechnology. An essential milestone in the realm of nanotechnology is the process of creating dependable and environmentally acceptable metallic nanoparticles. Due to its increasing popularity and ease, use of ambient biological resources is quickly becoming more significant in this field of study. The phrase "green nanotechnology" has gained a lot of attention and refers to a variety of procedures that eliminate or do away with hazardous compounds to repair the environment. Green nanomaterials can be used in a variety of biotechnological sectors such as medicine and biology, as well as in the food and textile industries, wastewater treatment and agriculture field. The construction of an updated level of knowledge with utilization and a study of the ambient biological systems that might support and revolutionize the creation of nanoparticles (NPs) are presented in this article.

Biosynthesis of Silver and Gold Nanoparticles and Their Efficacy Towards Antibacterial, Antibiofilm, Cytotoxicity, and Antioxidant Activities

The World Health Organization (WHO) reports that the emergence of multidrug-resistant and the slow advent of novel and more potent antitumor and antimicrobial chemotherapeutics continue to be of the highest concern for human health. Additionally, the stability, low solubility, and negative effects of existing drugs make them ineffective. Studies into alternative tactics to tackle such tenacious diseases was sparked by anticancer and antibacterial. Silver (Ag) and gold (Au) nanoparticles (NPs) were created from Trichoderma saturnisporum, the much more productive fungal strain. Functional fungal extracellular enzymes and proteins carried out the activities of synthesis and capping of the generated nano-metals. Characterization was done on the obtained Ag-NPs and Au-NPs through UV-vis, FTIR, XRD, TEM, and SEM. Additionally, versus methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Klebsiella pneumoniae, the antibacterial activities of Ag-NPs and Au-NPs were assessed. In particular, the Ag-NPs were more effective against pathogenic bacteria than Au-NPs. Furthermore, antibiofilm study that shown Au-NPs had activity more than Ag-NPs. Interestingly, applying the DPPH procedure, these noble metallic NPs had antioxidant activity, in which the IC₅₀ for Ag-NPs and Au-NPs was 73.5 μg/mL and 190.0 μg/mL, respectively. According to the cytotoxicity evaluation results, the alteration in the cells was shown as loss of their typical shape, partial or complete loss of monolayer, granulation, shrinking, or cell rounding with IC₅₀ for normal Vero cell were 693.68 μg/mL and 661.24 μg/mL, for Ag-NPs and Au-NPs, respectively. While IC₅₀ for cancer cell (Mcf7) was 370.56 μg/mL and 394.79 μg/mL for Ag-NPs and Au-NPs, respectively. Ag-NPs and Au-NPs produced via green synthesis have the potential to be employed in the medical industry as beneficial nanocompounds.

Green Synthesis and Antibacterial Activity of Ag/Fe2O3 Nanocomposite Using Buddleja lindleyana Extract

In the study reported in this manuscript, silver/iron oxide nanocomposites (Ag/Fe₂O₃) were phytosynthesized using the extract of Buddleja lindleyana via a green, economical and eco-friendly strategy. The biosynthesized Ag/Fe₂O₃ nanocomposites were characterized using UV-Vis spectrophotometry, FTIR, XRD, TEM, DLS and SEM-EDX analyses. The particulates showed a triangular and spherical morphology having sizes between 25 and 174 nm. FTIR studies on the nanoparticles showed functional groups corresponding to organic metabolites, which reduce and stabilize the Ag/Fe₂O₃ nanocomposite. The antimicrobial efficacy of the phytosynthesized Ag/Fe₂O₃ against bacterial pathogens was assessed. In addition, Ag/Fe₂O₃ exhibited broad spectrum activities against B. subtilis, S. aureus, E. coli, and P. aeruginosa with inhibition zones of 23.4 ± 0.75, 22.3 ± 0.57, 20.8 ± 1.6, and 19.5 ± 0.5 mm, respectively. The Ag/Fe₂O₃ composites obtained showed promising antibacterial action against human bacterial pathogens (S. aureus, E. coli, B. subtilis and P. aeruginosa), making them candidates for medical applications.

Synthesis of Silver Nanocomposite Based on Carboxymethyl Cellulose: Antibacterial, Antifungal and Anticancer Activities

Traditional cancer treatments include surgery, radiation, and chemotherapy. According to medical sources, chemotherapy is still the primary method for curing or treating cancer today and has been a major contributor to the recent decline in cancer mortality. Nanocomposites based on polymers and metal nanoparticles have recently received the attention of researchers. In the current study, a nanocomposite was fabricated based on carboxymethyl cellulose and silver nanoparticles (CMC-AgNPs) and their antibacterial, antifungal, and anticancer activities were evaluated. The antibacterial results revealed that CMC-AgNPs have promising antibacterial activity against Gram-negative (Klebsiella oxytoca and Escherichia coli) and Gram-positive bacteria (Bacillus cereus and Staphylococcus aureus). Moreover, CMC-AgNPs exhibited antifungal activity against filamentous fungi such as Aspergillus fumigatus, A. niger, and A. terreus. Concerning the HepG2 hepatocellular cancer cell line, the lowest IC₅₀ values (7.9 ± 0.41 µg/mL) were recorded for CMC-AgNPs, suggesting a strong cytotoxic effect on liver cancer cells. As a result, our findings suggest that the antitumor effect of these CMC-Ag nanoparticles is due to the induction of apoptosis and necrosis in hepatic cancer cells via increased caspase-8 and -9 activities and diminished levels of VEGFR-2. In conclusion, CMC-AgNPs exhibited antibacterial, antifungal, and anticancer activities, which can be used in the pharmaceutical and medical fields.

Unveiling Antimicrobial and Insecticidal Activities of Biosynthesized Selenium Nanoparticles Using Prickly Pear Peel Waste

In the current study, prickly pear peel waste (PPPW) extract was used for the biosynthesis of selenium nanoparticles through a green and eco-friendly method for the first time. The biosynthesized SeNPs were characterized using UV-Vis, XRD, FTIR, TEM, SEM, EDX, and mapping. Characterization results revealed that biosynthesized SeNPs were spherical, polydisperse, highly crystalline, and had sizes in the range of 10–87.4 nm. Antibacterial, antifungal, and insecticidal activities of biosynthesized SeNPs were evaluated. Results revealed that SeNPs exhibited promising antibacterial against Gram negative (E. coli and P. aeruginosa) and Gram positive (B. subtilis and S. aureus) bacteria where MICs were 125, 125, 62.5, and 15.62 µg/mL, respectively. Moreover, SeNPs showed potential antifungal activity toward Candida albicans and Cryptococcus neoformans where MICs were 3.9 and 7.81 µg/mL, respectively. Furthermore, tested crud extract and SeNPs severely induced larvicidal activity for tested mosquitoes with LC50 and LC90 of 219.841, 950.087 mg/L and 75.411, 208.289 mg/L, respectively. The fecundity and hatchability of C. pipiens mosquito were significantly decreased as applied concentrations increased either for the crude or the fabricated SeNPs extracts. In conclusion, the biosynthesized SeNPs using prickly pear peel waste have antibacterial, antifungal, and insecticidal activities, which can be used in biomedical and environmental applications.

Environmental Impacts of Ecofriendly Iron Oxide Nanoparticles on Dyes Removal and Antibacterial Activity

Biosynthesized nanoparticles have a promising future since they are a more environmentally friendly, cost-effective, repeatable, and energy-efficient technique than physical or chemical synthesis. In this work, Purpureocillium lilacinum was used to synthesize iron oxide nanoparticles (Fe₂O₃-NPs). Characterization of mycosynthesized Fe₂O₃-NPs was done by using UV-vis spectroscopy, transmission electron microscope (TEM), dynamic light scattering (DLS), and X-ray diffraction (XRD) analysis. UV-vis gave characteristic surface plasmon resonance (SPR) peak for Fe₂O₃-NPs at 380 nm. TEM image reveals that the morphology of biosynthesized Fe₂O₃-NPs was hexagonal, and their size range between 13.13 and 24.93 nm. From the XRD analysis, it was confirmed the crystalline nature of Fe₂O₃ with average size 57.9 nm. Further comparative study of photocatalytic decolorization of navy blue (NB) and safranin (S) using Fe₂O₃-NPs was done. Fe₂O₃-NPs exhibited potential catalytic activity with a reduction of 49.3% and 66% of navy blue and safranin, respectively. Further, the antimicrobial activity of Fe₂O₃-NPs was analyzed against pathogenic bacteria (Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, and Staphylococcus aureus). The Fe₂O₃-NPs were clearly more effective on gram-positive bacteria (S. aureus and B. subtilis) than gram-negative bacteria (E. coli and P. aeruginosa). Thus, the mycosynthesized Fe₂O₃-NPs exhibited an ecofriendly, sustainable, and effective route for decolorization of navy blue and safranin dyes and antibacterial activity.

Multifunctional Silver Nanoparticles Based on Chitosan: Antibacterial, Antibiofilm, Antifungal, Antioxidant, and Wound-Healing Activities

The purpose of this study is to create chitosan-stabilized silver nanoparticles (Chi/Ag-NPs) and determine whether they were cytotoxic and also to determine their characteristic antibacterial, antibiofilm, and wound healing activities. Recently, the development of an efficient and environmentally friendly method for synthesizing metal nanoparticles based on polysaccharides has attracted a lot of interest in the field of nanotechnology. Colloidal Chi/Ag-NPs are prepared by chemical reduction of silver ions in the presence of Chi, giving Chi/Ag-NPs. Physiochemical properties are determined by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) analyses. TEM pictures indicate that the generated Chi/Ag-NPs are nearly spherical in shape with a thin chitosan covering around the Ag core and had sizes in the range of 9–65 nm. In vitro antibacterial activity was evaluated against Staphylococcus aureus and Pseudomonas aeruginosa by a resazurin-mediated microtiter plate assay. The highest activity was observed with the lowest concentration of Chi/Ag-NPs, which was 12.5 µg/mL for both bacterial strains. Additionally, Chi/Ag-NPs showed promising antifungal features against Candida albicans, Aspergillus fumigatus, Aspergillus terreus, and Aspergillus niger, where inhibition zones were 22, 29, 20, and 17 mm, respectively. Likewise, Chi/Ag-NPs revealed potential antioxidant activity is 92, 90, and 75% at concentrations of 4000, 2000, and 1000 µg/mL, where the IC₅₀ of Chi/Ag-NPs was 261 µg/mL. Wound healing results illustrated that fibroblasts advanced toward the opening to close the scratch wound by roughly 50.5% after a 24-h exposure to Chi/Ag-NPs, greatly accelerating the wound healing process. In conclusion, a nanocomposite based on AgNPs and chitosan was successfully prepared and exhibited antibacterial, antibiofilm, antifungal, antioxidant, and wound healing activities that can be used in the medical field.

Powder and High-Solid Coatings

This Special Issue presents a series of research papers and reviews about the actual trend of powder and high solid coatings which show the advantage of great environmental sustainability by avoiding the massive use of organic solvents. Moreover, some very interesting studies exist on the move from a simple protective layer to a smart coating with additional properties, both for the aesthetic and functional aspects.

Potential of biosynthesized zinc oxide nanoparticles to control Fusarium wilt disease in eggplant (Solanum melongena) and promote plant growth

In this study, a novel, non-toxic, eco-friendly zinc oxide nanoparticles (ZnO-NPs) was used instead of the synthetic fungicides widely used to control the destructive phytopathogenic fungus Fusarium oxysporum, the causative agent of wilt disease in Solanum melongena L. Herein, the biosynthesized ZnO-NPs was carried out by Penicillium expansum ATCC 7861. In vitro, mycosynthesized ZnO-NPs exhibited antifungal activity against Fusarium oxysporum. In vivo, ZnO-NPs suppressed Fusarium wilt disease in cultivated Solanum melongena L. by decreasing the disease severity with 75% of plant protection. Moreover, ZnO-NPs stimulated the recovery of eggplant as an indicated by improving of morphological and metabolic indicators including plant height(152.5%), root length(106.6%), plant fresh biomass (146%), chlorophyll a (102.8%), chlorophyll b (67.86%), total soluble carbohydrates (48.5%), total soluble protein (81.8%), phenol (10.5%), antioxidant activity and isozymes compared with infected control. Therefore, this study suggests using mycosynthesized ZnO-NPs as an alternative to synthetic fungicides not only to eradicate the Fusarium wilt disease in cultivated eggplant (Solanum melongena) but also to promote the growth parameters and metabolic aspects.