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Remdesivir (RDV) is a drug that exhibits broad-spectrum antiviral against RNA viruses, and so this drug could be an appropriate therapeutic candidate. To increase the therapeutic efficiency of Remdesivir, nanoparticles are employed to prolong bioavailability and facilitate targeted delivery in the body and the drug transportation. In this study, we employed classical atomistic molecular dynamics simulations to characterize the adsorption properties of this compound on Ag nanoparticles. The simulation results show that Remdesivir molecules adsorb onto the surface of Ag nanoparticles in a size-dependent manner, so that smaller AgNPs exhibit a higher degree of Remdesivir coating than larger ones. The results also show that the coating of Remdesivir molecules on nanoparticles can improve their pharmacokinetic properties in vivo studies. These findings provide a basis for designing nanoparticle-based drug delivery systems. [ABSTRACT FROM AUTHOR]

The widespread use of synthetic polymers in various industries has raised worldwide concerns regarding their ecological impact and effects on human health. As a result, biopolymers have emerged as a promising alternative. Among them, exopolysaccharides (EPSs) produced by microbes from terrestrial niches have been extensively studied. However, recent reports have indicated that microbes from marine environments can also produce unique EPSs that could serve as sustainable substitutes to meet the escalating demand for biopolymers. The present study, for the first time, reports EPS production from novel marine bacterium Algoriphagus sp. K5R for sustainable application development. Interestingly, physicochemical analyses suggest that EPS K5R is a high molecular weight (1190.63 kDa) heteropolysaccharide composed of galacturonic acid, glucose and mannose. To evaluate EPS production, growth and fermentation kinetics were performed, which revealed that it was a primary metabolite having a maximum production of 4.79 ± 0.57 g L−1 with 2% (w/v) glucose. Moreover, EPS K5R exhibits exceptional functional properties, namely high water‐holding capacity (720% ± 80.29%) and oil‐holding capacity (493.33% ± 49.74% for coconut oil and 533.32% ± 17.47% for olive oil), and non‐Newtonian pseudo‐plastic behavior which render it a promising candidate for application in the cosmetics and food industries. In fact, its anti‐oxidant capabilities make it an ideal biological reducing agent for metal nanoparticle synthesis. Overall, this study highlights the potential of marine EPSs for a diverse array of industrial applications. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Nanoparticle-based products formed by combining atomic and molecular level materials find their place in many fields such as industry, cosmetics, medicine and pharmacy. In our study, we synthesised Ag NPs from mountain tea (Sideritis L.) using green chemistry method and demonstrated their material properties by characterisations such as SEM, EDX, FT-IR, XRD and UV–Vis spectroscopy. It was observed that the obtained silver nanoparticles formed inhibition zone diameters of 18 mm, 10 mm and 10 mm against Bacillussubtilis ATCC 6633, Pseudomonasaeruginosa ATCC 27853 and Staphylococcusaureus ATTC 29213 bacteria, respectively. Candidaalbicans ATTC 90028 pathogen, which we used as a fungus, formed a zone diameter of 10 mm. In addition the effect of Ag NPs against DNA damage was determined by gel electrophoresis method. In the images, it is seen that the damaged DNA in the 2 end well is preserved due to the increase in concentration. The effects of Ag NPs used in the 5th and 6 th wells are much better seen compared to the others. Ag NPs showed strong resistance to possible DNA damage. DPPH method was used to investigate the antioxidant effects of AgNPs produced by green synthesis, which is a biological procedure, and as a result, the radical quenching activity of mountain tea was found to be quite good with a value of 80% compared to the positive control BHA. We hope that Ag NPs synthesised from mountain tea, whose structure and properties have been extensively elucidated by various methods, may have a wide range of uses that can serve humanity. [ABSTRACT FROM AUTHOR]

The traditional physical and chemical methods used in the production of silver nanoparticles (AgNP) consist of complex, expensive, and environmentally harmful processes. To overcome these problems, researchers have turned to the AgNP production method called green synthesis or biosynthesis. This study aims to produce AgNPs by green synthesis from the extracts of Ulva lactuca and Halopteris scoparia and to determine their antibacterial and antifungal activities. In this context, the effects of some process parameters on nanoparticle size were examined statistically and the antimicrobial activities of AgNPs produced under optimum conditions against various pathogenic bacteria and fungi were determined. The smallest AgNPs synthesized from Ulva lactuca and Halopteris scoparia extracts were measured as 40.19 ± 5.93 and 34.88 ± 4.38 nm, respectively, under the conditions of pH of 11, AgNO3 ratio of 10%, and temperature of 55 °C. As for the antibacterial activity of AgNPs, the diameters of the inhibition zones formed against pathogenic bacteria were found as between 10 and 15 mm. As for the antifungal activity, a reduction between 15 and 21.33 mm was observed in pathogenic fungi growths. With this study, it was concluded that macroalgae can be easily used in the green synthesis of AgNPs with antibacterial and antifungal properties. Future research of green-synthesized AgNPs from macroalgae will be highly important for being used as an antibacterial and antifungal agent in fields such as medicine and cosmetics. [ABSTRACT FROM AUTHOR]

AbstractPlant-mediated silver nanoparticles (AgNPs) synthesis appears to be reliable and environmentally friendly, requiring less energy, and cost. Various components present in its natural products can function as strong reducing and capping substrates, ensuring the stability of the resulting NPs. This study synthesized AgNPs with root extracts of O. mutabilis. The effect of many different synthesis parameters (such as silver ion concentration, temperature and reaction pH) of the obtained root extract on the synthesis of AgNPs was also examined. Furthermore, AgNPs were characterized using UV-Vis spectroscopy, Fourier-transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), particle size measurement (Malvern Mastersizer) and energy dispersive X-ray analysis (EDX). The surface plasmon resonance band features of AgNPs were determined in the ultraviolet-visible absorbance spectrum at 410 nm. Total phenolic compound (TPC) determination was analyzed using the Folin-Ciocalteu method, and TPC in AgNPs extracts was determined as 295 ± 0.02 mg GAEs/gr extract. The antioxidant activity of the AgNPs was examined using the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) free radical scavenging activity method. The synthesized AgNPs exhibited strong antioxidant activity. The antidiabetic activity was determined by measuring alpha-amylase inhibition by spectrophotometric method. α-amylase inhibition values were determined to be highest at 31%. The study was further elaborated for determining AgNPs antibacterial using MIC. The biosynthesized AgNPs showed effective antibacterial activity against the Acinetobacter baumannii (A.baumannii) bacteria.Suggests that green biosynthesized AgNPs can constitute an effective antioxidant, antidiabetic and antibacterial agent. [ABSTRACT FROM AUTHOR]

We aimed to synthesize silver nanoparticles (AgNPs) using Elettaria cardamomum (cardamom) extracts and assess the cytotoxicity and genotoxicity of the cardamom extract, cardamom–AgNPs, and the insecticide ATCBRA—commonly used for pest control—on the root system of Vicia faba (broad bean). The chemical composition of the aqueous cardamom extract was identified and quantified using GC-MS, revealing a variety of bioactive compounds also present in cardamom essential oil. These included α-terpinyl acetate (21.3–44.3%), 1,8-cineole (10.7–28.4%), and linalool (6.4–8.6%). The successful green synthesis of AgNPs was confirmed through various micro-spectroscopic techniques, including UV-Vis spectroscopy, transmission electron microscopy (TEM), and energy-dispersive spectroscopy (EDS). UV-Vis analysis showed a strong peak between 420 and 430 nm, indicating the presence of AgNPs. TEM imaging revealed that the synthesized cardamom–AgNPs were monodispersed, primarily spherical, and semi-uniform in shape, with minimal aggregation. EDS analysis further confirmed the composition of the nanoparticles, with cardamom–AgNPs comprising around 60.5% by weight. Cytotoxicity was evaluated by measuring the mitotic index (MI), and genotoxicity was assessed by observing chromosomal aberrations (CAs). The roots of Vicia faba were treated for 24 and 48 h with varying concentrations of ATCBRA pesticide (0.1%, 0.3%, 0.5%, and 0.7%), aqueous cardamom extract (3%, 4%, 5%, and 6%), and green-synthesized cardamom–AgNPs (12, 25, and 60 mg). The cytogenetic analysis of MI and CA in the meristematic root tips indicated an improvement in the evaluated parameters with the cardamom extract. However, a marked reduction in mitotic activity was observed with both ATCBRA and cardamom–AgNP treatments across both time points, highlighting potential cytotoxic and genotoxic effects. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to evaluate and compare the antibacterial efficacy of nitrofurantoin (Nit) and calcium hydroxide (CH) coated with silver nanoparticle (AgNP) against Enterococcus faecalis -infected root canals using flow cytometry. Materials and Methods: Seventy-eight extracted noncarious human single-rooted teeth were decoronated and chemomechanical preparation was done. The decoronated roots were inoculated with E. Faecalis for 21 days. The roots were then grouped depending on the types of intracanal medicaments used, namely, Group 1: Nit paste; Group 2: Nit with 0.02% AgNP suspension; Group 3: CH paste (Ultracal); Group 4: CH paste with 0.02% AgNP suspension; Group 5: 0.02% AgNP suspension; and Group 6: normal saline (0.9%) was taken as control. After 14 days of incubation, dentin chips from root canals were retrieved and transferred into Eppendorf tubes containing distilled water, and flow cytometry analysis was done. The statistical analysis was done using ANOVA. Results: Flow cytometry analysis revealed that antibacterial activity of intracanal medicament was highest for Nit + AgNp. The least activity was observed for AgNP. Conclusion: Both Nit and Nit with 0.02% AgNP can be used as potential intracanal medicaments against E. faecalis. [ABSTRACT FROM AUTHOR]

High-sensitivity and repeatable detection of hydrophobic molecules through the surface-enhanced Raman scattering (SERS) technique is a tough challenge because of their weak adsorption and non-uniform distribution on SERS substrates. In this research, we present a simple self-assembly protocol for monolayer SERS mediated by 6-deoxy-6-thio-β-cyclodextrin (β-CD-SH). This protocol allows for the rapid assembly of a compact silver nanoparticle (Ag NP) monolayer at the oil/water interface within 40 s, while entrapping analyte molecules within hotspots. The proposed method shows general applicability for detecting hydrophobic molecules, exemplified as Nile blue, Nile red, fluconazole, carbendazim, benz[a]anthracene, and bisphenol A. The detection limits range from 10−6to 10−9 M, and the relative standard deviations (RSDs) of signal intensity are less than 10%. Moreover, this method was used to investigate the release behaviors of a hydrophobic pollutant (Nile blue) adsorbed on the nanoplastic surface in the water environment. The results suggest that elevated temperatures, increased salinities, and the coexistence of fulvic acid promote the release of Nile blue. This simple and fast protocol overcomes the difficulties related to hotspot accessibility and detection repeatability for hydrophobic analytes, holding out extensive application prospects in environmental monitoring and chemical analysis. [ABSTRACT FROM AUTHOR]

AbstractControlled polymerization of silver dispersed poly (aniline -co-3–Bromo Aniline) electroactive composites was synthesized by using soft template polymerization. The formation of complexes between silver nanoparticles (AgNPs) and a polyaniline matrix results in ordered nanostructured materials. In this study, we synthesized a new series of copolymer composites of silver-dispersed poly(aniline-co-3-bromoaniline) using an in-situ chemical oxidative polymerization method at different molar ratios of the monomers. The resulting composites were characterized by using UV–vis spectroscopy, FT–IR spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The optical absorption spectrum revealed peaks at 338 nm and 596 nm, attributed to π–π*and n–π* electronic transitions. FT–IR spectra confirmed the presence of benzenoid and quinoid rings within the copolymer system. XRD analysis indicated the amorphous nature of the copolymer and crystalline nature of metal nanoparticles, while SEM images displayed agglomerated spherical granular morphology with average particle sizes ranging from 150 to 300 nm with uniform dispersion of metal nanoparticles. The four probe electrical conductivity measurements shows an electroactive nature whose conductivity ranges from 1.13 × 10−5 to 5.16 × 10−8 S/cm. These nanocomposites possess enhanced electrical and optical properties compared to their individual components for industrial applications. [ABSTRACT FROM AUTHOR]

Production of nanoparticles (NPs) can be achieved through three main methods: physical, chemical, and biological. Among these, biological methods are particularly advantageous due to their low cost, ease of implementation, rapidity, non-toxicity, reproducibility, and environmentally friendly nature. Silver nanoparticles have garnered significant attention across various research fields owing to their diverse applications, including their antibacterial and antifungal properties. In this study, silver nanoparticles were synthesized utilizing an extract derived from Rumex alveolatus, and their antifungal effects against Aspergillus niger were investigated. The biologically synthesized silver nanoparticles were comprehensively characterized through optical, structural, morphological, and chemical analyses employing various techniques, such as UV–Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, particle size analysis (PSA), dynamic light scattering (DLS), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). The absorption spectra confirmed the successful synthesis of silver nanoparticles (AgNPs), evident from the surface plasmon resonance (SPR) peaks observed around 450 nm. The synthesized AgNPs exhibited notable inhibitory activity against A. niger. To assess the inhibitory effect of the nanoparticles on A. niger growth, the fungi were cultured in a medium containing varying concentrations of nanoparticles ranging from 25 to 400 ppm. The results revealed that the synthesized AgNPs exhibited a spherical morphology with sizes ranging from 25 to 100 nm. Furthermore, it was observed that silver nanoparticles exerted the most significant inhibitory effect at concentrations of 200 and 400 ppm. [ABSTRACT FROM AUTHOR]

Biosurfactants prevent agglomeration of nanoparticles by reducing the surface tension and offer stability over time by forming a stable layer on the surface of nanoparticles. The current study focuses on the biosynthesis of silver nanoparticles (SNP) coated with a rhamnolipid biosurfactant (BS) and its use as an additive in fabric cleaning detergent. Rhamnolipids were extracted from a Pseudomonas aeruginosa strain, Pa84, that was isolated from a halophilic environment, Sambhar Salt Lake, Rajasthan, India. The reduction of silver ions was achieved by the rhamnolipid‐coated SNP (BS‐SNP). BS, SNP, and BS‐SNP demonstrated antibacterial efficacy against a variety of microorganisms. Lipase, present in the crude biosurfactant, was immobilized on modified chitosan microbeads (Ch‐BS‐SNP) and used for washing fabrics. The conjugate was found to be effective as a laundry detergent additive. The immobilized lipase showed high relative activity ranging from 66% to 110% and performed better than free lipase or standards. Our results highlight a potential claim for a commercially viable laundry detergent additive. [ABSTRACT FROM AUTHOR]

In this research, the antimicrobial properties of zinc oxide (ZnO NPs) and silver (AgNPs) nanoparticles, synthesized biologically using Neowestiellopsis persica through various methods (such as wet biomass, boiling biomass, supernatant, extracellular polysaccharides, and phycocyanin), were examined against fish pathogens including Aeromonas hydrophila, Edwardsiella tarda, Yersinia enterocolitica, and Pseudomonas putida. The nanoparticles were successfully created using all methods and characterized employing techniques like UVvisible spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS). The antibacterial activity of the nanoparticles was assessed using agar-well diffusion assays, while transmission electron microscopy (TEM) was utilized to analyze the ultrastructural interactions between the nanoparticles and the pathogens. Cytotoxicity was evaluated via the trypan blue exclusion method. Notably, nanoparticles generated through the boiling-biomass method demonstrated significantly enhanced characteristics. The analysis revealed two distinct populations of AgNPs measuring 78.82 nm (41.2%) and 91.28 nm (45.5%), along with a pronounced absorption peak at 68.6 nm (80.1%) for ZnO NPs. AgNPs exhibited the strongest growth inhibition against Pseudomonas putida and Edwardsiella tarda, whereas ZnO NPs showed the largest inhibition zone against Yersinia enterocolitica, Pseudomonas aeruginosa, and Aeromonas hydrophila. TEM imagery illustrated the binding of nanoparticles to the outer membranes of Yersinia enterocolitica, compromising their structural integrity. The application of 25 µg/ml of AgNPs and 6.25 µg/ml of ZnO did not lead to significant cell death, but higher concentrations resulted in a dose-dependent cytotoxic effect. Ultimately, the findings of this study confirm that the antibacterial and cytotoxic attributes of silver and zinc oxide nanoparticles, produced through the biosynthesis of Neowestiellopsis persica A1387, can be leveraged to meet future needs in aquaculture. [ABSTRACT FROM AUTHOR]

In recent years, thin-film silicon solar cells have garnered significant attention due to their low manufacturing costs, yet their efficiency remains relatively low owing to their limited absorption capacity. The primary approach to enhancing the absorption of thin-film solar cells involves the utilization of plasmonic nanoparticles. In this study, we designed a graphene-coated silver nanoparticle (GCSNP) for this purpose. We modeled its permittivity using the Kubo formula and an equivalent dielectric permittivity model. Our nanoparticle size was deliberately chosen to be significantly smaller than the resonance wavelength, allowing it to be treated as an isotropic homogeneous particle. The inherent plasmonic properties of nanoparticles can enhance the efficiency of photovoltaic cells by increasing their scattering cross-section. We computed the scattering cross-section of GCSNP through numerical solutions and optical simulations for graphene thicknesses ranging between 0.34 and 1 nm. Based on the scattering peak, we optimized the graphene coating thickness to be 0.8 nm. Subsequently, we embedded GCSNPs, each with a graphene thickness of 0.8 nm, within the absorber layer of a Si-based thin-film solar cell and analyzed its properties using the FDTD method. Compared to a similar cell designed with silver nanoparticles, our cell exhibited a 20.6% increase in absorption and a 7.3% rise in short-circuit current density. Finally, we investigated the impact of the geometry and dimensions of GCSNPs on the performance of Si-based thin-film solar cells, determining that a cylindrical shape with a diameter and height of 50 nm each serves as the optimized GCSNP. [ABSTRACT FROM AUTHOR]

The choice of plant species is crucial, as different plants provide unique biomolecules that influence nanoparticle characteristics. Biomolecules in plant extracts, such as proteins, amino acids, enzymes, polysaccharides, alkaloids, tannins, phenolics, saponins, terpenoids, and vitamins, act as stabilizing and reducing agents. This study explores the synthesis of silver nanoparticles (AgNPs) using leaf extracts from collard greens (Brassica oleracea var. acephala), hazelnut (Corylus avellana var. avellana), and green tea (Camellia sinensis). NPs were synthesized using silver nitrate (AgNO3) solution at two different molarities (1 mM and 5 mM) and characterized by UV–Vis spectroscopy, XRD, TEM, and FTIR. The Surface Plasmon Resonance (SPR) peaks appeared rapidly for hazelnut and green tea extracts, within 30 and 15 min, respectively, while collard greens extract failed to produce a distinct SPR peak. X-Ray Diffraction confirmed the formation of face-centered cubic silver. TEM analysis revealed high polydispersity and agglomeration in all samples, with particle size generally decreasing at higher AgNO3 concentrations. However, hazelnut extract showed a slight increase in size at higher molarity. Among all samples, green tea-derived AgNPs synthesized with 5 mM AgNO3 were the smallest and least polydisperse, highlighting the significant role of plant type in optimizing nanoparticle synthesis. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) doesn't have well-defined molecular targets making it unable to treat with chemotherapy also have faster metastatic rate and worse survival rate. In the current study we aim to target TNBC through eco-friendly green synthesized silver nanoparticles having anti-cancer phytoconstituents from the traditional anti-cancer medicinal plant Eclipta alba. Green synthesized silver nanoparticles (AgNPs) are agglomerates of spherical shaped 40-60 nm sized showing characteristic light absorption at 437 nm, banding pattern at 1479, 1285, 1036, and 471 showing and further X-ray diffraction pattern confirm face-centered cubic crystal silver structure exist in the green synthesized silver nanoparticle preparation. Further in vitro anti-oxidant analysis results revealed that green synthesized AgNPs showed 2.6-fold higher anti-oxidant potential (IC50 15.70 g/ml) than that of aqueous plant leaf extract (IC50 39.80 g/ml). In MTT cytotoxicity analysis Eclipta alba plant extract and AgNPs both display dose-dependent cytotoxicity against triple-negative breast cancer cells (MDA-MB-231), although their IC50 values differ substantially, at 105.80 µg/ml and 77.20 g/ml, respectively. Finally, AgNPs from Eclipta alba tested for anti-leishmanial activity and it showed 91.36 ± 1.05 for promastigotes and 76.62 ± 0.95 for amastigotes at the highest dose of 400 g/ml. Altogether present data showed that Eclipta alba leaf extract actively bonded with silver nanoparticles suppresses the MDA-MB-231 cells growth through high antioxidant characters and anti-leishmanial activity. From together we confirm that Eclipta alba was recommended to a future therapeutic drug and agent to control breast cancer in the clinical level. [ABSTRACT FROM AUTHOR]