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The use of nanoparticles (NPs) as an alternative to the current generation of conventional antibiotics has exploded in the research community in recent years, as evidence of the superiority of NPs over antibiotics in the treatment of pathogens has been steadily presented. However, therapy with NPs may result in the removal of both multidrug-resistant (MDR) pathogens and commensal bacteria due to the broad-spectrum activity of NPs and the non-specificity of target bacteria. Therefore, the fabrication of MDR-pathogen-targeting NPs is necessary. In this study, biogenic silver nanoparticles (Bio-AgNPs) were synthesized using bacterial cell-free supernatant from three communicating gram-negative bacteria. The size, physical features, and morphology of the AgNPs were characterized by dynamic light scattering (an average size of 158–168 nm), X-ray diffraction (co-ordinate patterns), and transmission electron microscopy (spherical structure). The antibacterial activity of the Bio-AgNPs as minimum inhibitory concentration values was obtained between 0.8 and > 6.4 μg mL−1 for bacterial strains. Mechanistic studies of Bio-AgNPs have revealed that biofilm inhibition, protein leakage, hyperproduction of reactive oxygen species, and physical cell damage are plausible mechanisms underlying the activity of Bio-AgNPs against gram-negative pathogens. Overall, the Bio-AgNPs synthesized in this study may bolster the potential use of Bio-AgNPs as a stand-in for traditional antibiotics, and offer potential specificity against bacterial targets. [ABSTRACT FROM AUTHOR]

Syzygium caryophyllatum (L.) Alston, an ethnobotanically acclaimed antidiabetic plant, was utilized for the first time in this study to synthesize silver nanoparticles (SC-AgNPs). Characterization revealed spherical SC-AgNPs (∼30 nm) with a silver content of 49.10 %, displaying diverse functional groups and significant antibacterial activity against Staphylococcus aureus and Proteus vulgaris. SC-AgNPs exhibited notable antidiabetic properties by inhibiting α-amylase and α-glucosidase activities, while enhancing glucose uptake in L6 and yeast cells. Moreover, SC-AgNPs demonstrated profound antioxidant activities by scavenging reactive oxygen species, which led to increased catalase activity and decreased glutathione-S-transferase activity. These properties surpassed those of the plant extract. SC-AgNPs were found to show low toxicity towards L6 cells when compared to the contemporary silver nanoparticles. The eco-friendly synthesis method and comprehensive biological assessments highlight the value of this work in advancing nanomedicine for diabetes management. [Display omitted] • First report of AgNPs synthesized using S. caryophyllatum leaves (SC-AgNPs). • SC-AgNPs inhibit α-amylase, α-glucosidase and enhances glucose uptake. • SC-AgNPs scavenges ROS and regulate CAT and GST. • SC-AgNPs exhibit antibacterial effects against S. aureus and P. vulgaris. [ABSTRACT FROM AUTHOR]

Nanoparticle synthesis under environmentally friendly conditions has been conducted utilizing natural resources in order to reduce the reliance on hazardous chemicals. For example, the utilization of microbial synthesis has enabled the production of nanoparticles that exhibit biocompatibility, stability, and safety. Microorganisms facilitate the growth of crystals while preventing aggregation. They serve as both reducing agents and capping agents by offering enzymes, peptides, poly(amino acids), polyhydroxyalkanoate, and polysaccharides. In this review, we present an overview of nanoparticle synthesis based on microorganisms including bacteria, fungi, algae, and actinobacteria, encompassing metals such as gold (Au), silver (Ag), platinum (Pt), palladium (Pd), copper (Cu), titanium dioxide ((TiO2), zinc oxide (ZnO), iron oxide (Fe2O3), and selenium (Se). The nanoparticles typically vary in size from 1 to 100 nm and exhibit various shapes including spherical, rod-shaped, triangular, cubic, and hexagonal shapes. Additionally, this review discusses the mechanisms behind the synthesis of metal nanoparticles by microorganisms, whether they occur intracellularly or extracellularly. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are employed to utilize plasmonic effects in PM6:Y7 organic solar cell. Such enables utilization of wavelengths ranging from 400–490 nm and resonance tuning toward longer wavelengths. Inverted structure is employed with AgNPs incorporated into zinc oxide (ZnO) layer. 5–15% volume ratio concentrations of AgNPs were used. The results obtained indicated a 12.97% power conversion efficiency for AgNPs with 10% concentration in comparison to the device without AgNP incorporation. Finite-difference time-domain method (FDTD) simulation of AgNP indicated forward scattering as the most dominant mechanism for external quantum efficiency (EQE) enhancements for wavelengths ranging from 500-900nm. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries (LIBs) are widely used as important energy storage and energy supply devices. The porous design and heteroatomization modification of carbon-based anode materials are crucial for achieving high-capacity and reversible energy storage in LIBs. Sol-gel method and pyrolysis treatment were used to obtain silica/silver composite particles used as templates. Polyphosphazene-coated silica/silver composite composite carbon materials (SiO2/Ag@PZS-C) were synthesized through in-situ self-assembly and carbonization of polyphosphazene. The electrochemical behavior and lithium storage mechanism of SiO2/Ag@PZS-C was also studied. The results reveal that the composite exhibited high specific capacity, stable cycling and superior rate performance. The double modification of silver nanoparticles and polyphosphazene carbon significantly improves the conductivity of silica and reduces the volume change. Moreover, the carbon shell of polyphosphazene facilitated the formation of a stable solid electrolyte interface film (SEI), preventing direct contact between the active material and the electrolyte, thereby substantially enhancing lithium storage performance. [ABSTRACT FROM AUTHOR]

Glass coatings find application across diverse fields, offering chemical resistance, insulation, and hardness to substrates. Toughness enhancement of glass coatings is strongly required to maintain these functions in the practical applications. In this study, we propose a novel approach to improve fracture toughness of glass coating by incorporating silver particles into it prepared via the sol-gel method. Samples with 0–2.0 vol% of 73 nm and 730 nm Ag particles in the precursor solution were obtained. The resulting samples exhibited high transparency, minimal change in Young's modulus, and considerably improved fracture toughness. At 73 nm and 730 nm, the maximum fracture toughness occurred at 0.5 vol% and 1.0 vol%, respectively, with a 1.4- and 1.8-fold increase compared to the original coating. This approach shows promise for enhancing glass coating toughness with minimal additive amounts and negligible loss of coating properties. [ABSTRACT FROM AUTHOR]

The prevalence of bacterial infections in hospitals is rising, endangering currently accessible, efficient medical treatments and increasing demand for novel medications. Metal nanoparticles (NPs) are showing promise as materials for the development of treatments and preventative measures. This study investigated the potential of the fungus Aspergillus terreus to produce silver nanoparticles (AgNPs) as a means of creating green technology to synthesize NPs. The synthesis parameters were optimized using the central composite design (CCD). The formation of AgNPs by fungal biomass was confirmed by absorption spectroscopy, FTIR, powder XRD, scanning electron microscopy, and transmission electron microscopy. The antibacterial properties of the AgNPs were tested against three nosocomial drug-sensitive bacterial strains and their drug-resistant variants, vancomycin-resistant Enterococcus faecalis, and the multidrug-resistant Pseudomonas aeruginosa and Acinetobacter baumannii. The prepared AgNPs demonstrated good efficacies against the pathogens studied, and they merit further investigation to find treatments for infections caused by drug-resistant nosocomial pathogens. [ABSTRACT FROM AUTHOR]

Survivin belongs to a family of proteins that promote cellular proliferation and inhibit cellular apoptosis. Its overexpression in various cancer types has led to its recognition as an important marker for cancer diagnosis and treatment. In this work, we compare two approaches for the immunochemical detection of survivin through surface-enhanced fluorescence or Raman spectroscopy using surfaces with nanowires decorated with silver nanoparticles in the form of dendrites or aggregates as immunoassays substrates. In both substrates, a two-step non-competitive immunoassay was developed using a pair of specific monoclonal antibodies, one for detection and the other for capture. The detection antibody was biotinylated and combined with streptavidin labeled with rhodamine for the detection of surface-enhanced fluorescence, while, for the detection via Raman spectroscopy, streptavidin labeled with peroxidase was used and the signal was obtained after the application of 3,3′,5,5′-tetramethylbenzidine (TMB) precipitating substrate. It was found that the substrate with the silver dendrites provided higher fluorescence signal intensity compared to the substrate with the silver aggregates, while the opposite was observed for the Raman signal. Thus, the best substrate was used for each detection method. A detection limit of 12.5 pg/mL was achieved with both detection approaches along with a linear dynamic range up to 500 pg/mL, enabling survivin determination in human serum samples from both healthy and ovarian cancer patients for cancer diagnosis and monitoring purposes. [ABSTRACT FROM AUTHOR]

Background: Anti-cariogenic properties of silver nanoparticles and fluorides have been probed mainly in vitro and with the objetive to evaluate the remineralizing effects of an applied silver nanoparticle compound plus fluoride varnish, a randomized split-mouth clinical trial was conducted in children aged 6 to 7 years. Methods: The project was approved by the ethics committee of the faculty. Primary molars were randomly distributed into two groups, as follows: Group A was treated with a compound based on silver nanoparticles plus fluoride varnish (SNP-FV), and Group B was treated with a silver diamine fluoride compound (SDF-KI), which is the current standard treatment. Laser fluorescence with a DIAGNOdent pen was used for the evaluation, with follow-up examinations at 15 days, 6 months, and 12 months. ANOVA test was used to compare the groups. The results showed a decrease in demineralization was observed after treatment with SNP-FV; similar results were observed after treatment with SDF-KI. Within each group, there were favorable changes. In the SDF-KI group, the differences in demineralization were 25.63 at 15 days, 29.37 at 6 months, and 30.6 at one year (p < 0.05). Meanwhile, in the SNP-FV group, the decreases were 22.7 at 15 days, 28.78 at 6 months, and 31.11 at one year (p < 0.05). Conclusions: The SNP-FV combined treatment represents an alternative remineralizing treatment for the management of carious lesions in the dentin of primary molars. [ABSTRACT FROM AUTHOR]

Lithium niobate perovskite and silver nanoparticle-based nanocomposites (LNB:AgNPs) were explored for developing an electrochemical glucose sensor. The perovskite to silver nanoparticle ratios investigated were 4:1, 1:1, 1:2, 2:1, and 1:4. Among these, the 4:1 ratio, with the lowest silver content, demonstrated the most stable performance during glucose quantification via amperometry. The sensor's response was evaluated measuring the current at a fixed potential of 0.7 V following the injection of 1 mM glucose with each addition. The calibration curve obtained from the recorded data exhibited a linear response within the 1 to 15 mM glucose concentration range, achieving a sensitivity of 2 μA/mM, a high correlation coefficient (R2 = 0.997), and a limit of detection (LOD) of 0.5 µM. The LNB4:1AgNP composite allowed taking advantage of the unique properties of both components in a balanced manner, maximizing the sensor performance in practical applications. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (Ag NPs) conjugated with amino-functionalized cellulose nanofibrils (NH2−CNFs) were in situ-prepared by reducing silver ions with free amino groups from NH2−CNFs. The spectroscopy and transmission electron microscopy measurements confirmed the presence of non-agglomerated nanometer-in-size Ag NPs within micrometer-large NH2−CNFs of high (20 wt.-%) content. Although the consumption of amino groups during the formation of Ag NPs lowers the ζ-potential and surface charge of prepared inorganic–organic hybrids (from +31.3 to +19.9 mV and from 2.4 to 1.0 mmol/g at pH 7, respectively), their values are sufficiently positive to ensure electrostatic interaction with negatively charged cell walls of pathogens in acidic and slightly (up to pH ~8.5) alkaline solutions. The antimicrobial activity of hybrid microparticles against various pathogens (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans) is comparable with pristine NH2−CNFs. However, a long-timescale use of hybrids ensures the slow and controlled release of Ag+ ions to surrounding media (less than 1.0 wt.-% for one month). [ABSTRACT FROM AUTHOR]

Currently, there are quite a few data on the ways silver nanoparticles get into the aquatic environment, on their subsequent dissolution in water, and on the release of toxic Ag+ ions. Differences in the experimental conditions hinder the determination of the basic regularities of this process. In this study, the stages of oxidative dissolution of AgNPs were studied, starting from the formation of silver hydrosol in deaerated solution, the reaction of silver with oxygen and with drinking and natural waters, the analysis of intermediate species of the oxidized colloidal particles, and the subsequent particle aggregation and precipitation, by optical spectroscopy, DLS, TEM, STEM, and EDX. In the presence of oxygen, silver nanoparticles undergo oxidative dissolution, which gives Ag+ ions and results in the subsequent aggregation of nanoparticles. The carbonate hydrosol loses stability when mixed with waters of various origin. This is due to the destruction of the electric double layer, which is caused by an increase in the solution's ionic strength and the neutralization of the charge of the metal core. The environmental hazard of the silver nanoparticle hydrosol would noticeably change and/or decrease when the nanoparticles get into natural waters because of their fast precipitation and because the major part of released Ag+ ions form poorly soluble salts with ions present in water. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles (AgNPs) were synthesized using a green method from an extract of the edible insect Oxya chinensis sinuosa (O_extract). The formation of AgNPs (O_AgNPs) was confirmed via UV–vis spectroscopy, and their stability was assessed using Turbiscan analysis. The size and morphology of the synthesized particles were characterized using transmission electron microscopy and field-emission scanning electron microscopy. Dynamic light scattering and zeta potential analyses further confirmed the size distribution and dispersion stability of the particles. The average particle size was 111.8 ± 1.5 nm, indicating relatively high stability. The synthesized O_AgNPs were further characterized using X-ray photoelectron spectroscopy (XPS), high-resolution X-ray diffraction (HR-XRD), and Fourier transform infrared (FTIR) spectroscopy. XPS analysis confirmed the chemical composition of the O_AgNP surface, whereas HR-XRD confirmed its crystallinity. FTIR analysis suggested that the O_extract plays a crucial role in the synthesis process. The antibacterial activity of the O_AgNPs was demonstrated using a disk diffusion assay, which revealed effective activity against common foodborne pathogens, including Salmonella Typhimurium, Escherichia coli, Staphylococcus aureus, and Bacillus cereus. O_AgNPs exhibited clear antibacterial activity, with inhibition zones of 15.08 ± 0.45 mm for S. Typhimurium, 15.03 ± 0.15 mm for E. coli, 15.24 ± 0.66 mm for S. aureus, and 13.30 ± 0.16 mm for B. cereus. These findings suggest that the O_AgNPs synthesized from the O_extract have potential for use as antibacterial agents against foodborne bacteria. [ABSTRACT FROM AUTHOR]

Hybrid nanoforms based on silver and the antibacterial drug dioxidine (2,3-bis-(hydroxymethyl)quinoxaline 1,4-di-N-oxide) are prepared by the method of joint cocondensation of metal and ligand vapors on a liquid nitrogen-cooled surface. The samples obtained are characterized by FTIR-, UV-Vis, and XPS-spectroscopy, as well as ТЕМ, SEM, and powder X-ray phase analysis (ХРА). It is shown that cryomodified nanoforms preferably consist of the anhydrous triclinic (T-phase) crystal phase of dioxidine. The dimensions of dioxidine particles ranged from 50 to 300 nm and the average size of doping silver nanoparticles is 15 ± 3 nm. The broadening of the diffraction patterns belonging to silver shows the transition of metallic silver to the nanoscale state. The FTIR results indicate hybrid nanoforms stabilized by the donor-acceptor interactions of surface silver atoms with the hydroxyl groups and with the donor N-atoms of quinoxaline cycles of dioxidine molecules. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The demand for superhydrophobic fabric with self‐cleaning and antibacterial features as potential practical applications has been rising steadily with the passage of time. In this research work, the wet chemical method is used to manufacture cotton with a superhydrophobic coating. Thus, Nanoparticles of silver were produced by using an in situ method. Afterward, the fabric is treated with a solution of perfluorooctyltriethoxysilane to make it superhydrophobic. The cotton fabric performs remarkably with exceptional hydrophobicity as it had a contact angle of 157 ± 1° and less than 10° in sliding angle. Water droplet's dynamic behavior is also studied so that the superhydrophobic fabric development can be proven. The fabric shows excellent chemical durability by performing chemical tests. The antimicrobial and self‐cleaning properties are greatly enhanced by the superhydrophobic coating on cotton. Particle density on the superhydrophobic cotton before and after self‐cleaning was found 5.1 and 0.4 mg/cm2. In addition, the treated cotton fabric also exhibited superior antibacterial properties against Escherichia coli bacteria. Therefore, the developed multifunctional cotton fabric can be used in real‐life applications. Highlights: Cotton fabric enables to repelling of dirt, oil, and water‐based stains more effectively.Silver nanoparticles possess potent antibacterial properties.Incorporation of PFOTS controls the release of silver into the environment.Versatile applications from healthcare and hospitality to outdoor and athletic apparel. [ABSTRACT FROM AUTHOR]

Nanotechnology is emerging as a promising tool to enhance traditional cancer treatments due to rising chemotherapy resistance and the severe side effects of toxic drugs. Silver nanoparticles (AgNPs) are widely acknowledged for their antimicrobial and antiproliferative properties. Given these AgNP characteristics, this research conducts a comprehensive nanotoxicological assessment of strategic combinations involving AgNPs (68 nm) commercial formulation and tamoxifen on MCF‐7 and MDA‐MB‐231 breast tumor cells. Utilizing CompuSyn software, the combination index was determined, revealing a synergistic cytotoxic and antiproliferative effect in AgNPs and tamoxifen combinations (CI < 0.97). Furthermore, this combination impaired cell migration (the scratch zone expanded by over 270%) and significantly increased reactive oxygen species production (up to 96% for MDA‐MB‐231 and 52% for MCF‐7 cells). Surprisingly, the genotoxic effect of these mixtures was minimal (below the allowable genotoxicity index of 1.5). Additionally, both breast tumor cell lines exhibited increased proapoptotic and oxidative stress gene expression following the combined treatment. The internalization of AgNPs into breast cancer cells was observed, enhancing their synergistic antiproliferative effect when combined with tamoxifen. These findings suggest the potential of combining AgNPs with chemotherapeutic agents for innovative studies in oncology therapy. Highlights: Small silver nanoparticles (AgNP) and tamoxifen mix is no‐genotoxic and boosts synergistic cytotoxicity.AgNPs and tamoxifen combo overexpress proapoptotic and oxidative stress genes.Tamoxifen's antiproliferative effect ramps up via AgNPs inducing oxidative stress.AgNPs internalized by breast cancer cells heighten antiproliferative effect. [ABSTRACT FROM AUTHOR]

Static self‐assembly resides in thermodynamically stable global minima of the energy landscape, whereas dynamic self‐assembly occupies local minima of the energy profile and remains in the ordered state for a limited time via dissipation of energy to surroundings. This makes the spatiotemporal control over the assembly and disassembly mechanism easily controllable in the case of dynamic self‐assembly. However, due to the higher thermal stability of static self‐assembly, it is very challenging to perform reverse engineering on these types of systems. Herein we report growth reaction‐based reversal of static silver cubes obtained via cucurbit[8]uril (CB[8]) crosslinked self‐assembly of silver nanoparticles (AgNP). The AgNP building units with variable CB[8] surface coverage have been used as seeds onto which deposition of gold via growth reaction has been performed. The disassembly of supracube structure has been controlled by the formation of [AuCl4]−–CB[8] complex and successive reduction of [AuCl4]− to Au0 on the surface of the seed. The resulting monodispersed isotropic nanoparticles, formed from the CB[8] based cubic self‐assembly after growth, exhibit Au−Ag bimetallic nature. Quenching of the fluorogenic response from the hydrophobic dye coumarin‐7, added after growth, suggests direct interaction with the metallic nanoparticle surface after disassembly and thereby confirms successful growth reaction mediated reversal of self‐assembly. [ABSTRACT FROM AUTHOR]

Background: Cotton leaf curl virus disease (CLCuD) is one of the major concerns for cotton growers. The traditional approach to managing CLCuD involves the control of the vector (whitefly) population through the use of pesticides. This study compares the efficacy of zinc oxide, iron oxide, copper and silver nanoparticles with conventional pesticides. Nanoparticles dose was optimized by evaluating their phytotoxic threshold in our previous study. In this study, optimized doses of nanoparticles such as zinc oxide (100 ppm), iron oxide (50 ppm), copper (50 ppm) and silver nanoparticles (25 ppm) were applied in a field trial of cotton against cotton leaf curl virus disease (CLCuD). Morphological parameters (height of stem, monopodial branches, sympodial branches, staple length, boll weight and number of bolls), yield parameters (seed cotton yield and ginning outturn), chlorophyll content (chlorophyll a, chlorophyll b, carotenoids and total chlorophyll), biochemical parameters (superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), catalase (CAT), hydrogen peroxide (H2O2) and electrolyte leakage) and disease parameters (reduction infection, disease severity and disease incidence) were determined in this study. Results: The incidence of cotton leaf curl virus was confirmed by triple antibody sandwich–enzyme-linked immunosorbent assay (TAS-ELISA). The pesticide Imidacloprid significantly reduced the infection by 79.3%. However, in comparison to pesticide, application of nanoparticles also reduced the infection. ZnO NPs reduced the infection by 42.33%, FeO NPs by 41%, Cu NPs by 34.7%, and Ag NPs by 44.8%. Moreover, these nanoparticles also improved the plant growth parameters as compared to control treatment. ZnO NPs enhanced morphological, yield parameters, and chlorophyll content by 36%, 22%, and 29%, respectively. FeO NPs showed improvements by 38%, 21%, and 29%; Cu NPs 39%, 25%, and 29%; and Ag NPs 31%, 19%, and 18%, respectively. Conclusion: Although treatment pesticide showed the least disease incidence compared to nanoparticles, nanoparticles are eco-friendly and safe as compared to pesticides. Farmers can apply these nanoparticles at their optimal thresholds through foliar application as an alternative to traditional pesticides. It is concluded that nanocomposites and hybrid modes may be used for managing CLCuD efficiently in the future. [ABSTRACT FROM AUTHOR]

We suggest sensor systems based on silver nanoparticles embedded within the polymethacrylate matrix for colorimetric determination of hydrogen peroxide. Polymethacrylate matrix stabilizes silver nanoparticles and its application enhances the selectivity of H2O2 determination through the transfer of the redox reaction from the solution volume into the solid phase, which reduces the access of interfering substances to the reaction medium. Dual-signal spectrophotometric and colorimetric approaches can be used for the determination of hydrogen peroxide in the range 0.2–4.4 mM with a detection limit 0.05 mM. We studied the conditions of interaction between the matrix components and some other substances by evaluating the influence of such factors as solution pH, the amount of nanoparticles within the polymer matrix, the contact time, and the analyte concentration upon the analytical signal. [ABSTRACT FROM AUTHOR]

Biologically produced silver nanoparticles are becoming a more appealing option than chemically produced antioxidants and antimicrobial agents, because they are safer, easier to manufacture and have medicinal properties at lower concentrations. In this work, we employed the aqueous pomegranate peel extract (PPE) to synthesize silver nanoparticles (PPE-AgNPs), as peel extract is a rich source of phytochemicals which functions as reducing agent for the synthesis of PPE-AgNPs. Additionally, the PPE was examined quantitatively for total phenolics and total flavonoids content. PPE-AgNPs were characterized using analytical techniques including UV–Vis spectroscopy, DLS, FTIR, XRD, HRTEM and FESEM, evaluated in vitro against the plant pathogenic microbes and also for antioxidant activities. Analytical techniques (HRTEM and FESEM) confirmed the spherical shape and XRD technique revealed the crystalline nature of synthesized PPE-AgNPs. Quantitative analysis revealed the presence of total phenolics (269.93 ± 1.01 mg GAE/g) and total flavonoids (119.70 ± 0.83 mg CE/g). Biosynthesized PPE-AgNPs exhibited significant antibacterial activity against Klebsiella aerogenes and Xanthomonas axonopodis, antifungal activity against Colletotrichum graminicola and Colletotrichum gloesporioides at 50 µg/mL concentration. The antioxidant potential of biosynthesized PPE-AgNPs was analysed via ABTS (IC50 4.25 µg/mL), DPPH (IC50 5.22 µg/mL), total antioxidant (86.68 g AAE/mL at 10 µg/mL) and FRAP (1.93 mM Fe(II)/mL at 10 µg/mL) assays. Cytotoxicity of PPE-AgNPs was valuated using MTT assay and cell viability of 83.32% was determined at 100 µg/mL concentration. These investigations suggest that synthesized PPE-AgNPs might prove useful for agricultural and medicinal purposes in the future. [ABSTRACT FROM AUTHOR]

The current situation involves an increase in interest in nanotechnology, in particular the ways in which it can be applied in the commercial and medical fields. However, traditional methods of synthesizing nanoparticles have some drawbacks, including the generation of harmful byproducts, high energy consumption, and cost. As a result, researchers have shifted their focus to "green" nanoparticle synthesis to circumvent these drawbacks. Because of their exceptional physiochemical properties, silver nanoparticles (Ag Nps) are the noble metal nanoparticles that are used most frequently. The green approach to Ag NP synthesis is environmentally friendly, non‐toxic, and cost‐effective, and it makes use of a variety of biological entities. Cyanobacteria, in particular, have garnered the most attention because of the abundance of bioactive substances that they contain, which serve both as reducing agents and as stabilizing agents during the process of biosynthesis. This review article discusses the current state of cyanobacteria‐mediated Ag NP synthesis, the potential mechanisms that are involved, nanoparticle characterization, the various applications of Ag NP in different fields, and their prospects. [ABSTRACT FROM AUTHOR]

The objective of the present study was the biosynthesis of nonhazardous and cost-effective silver nanoparticles (AgNPs) using plant extracts of Azadirachta indica (neem), for the removal of hexavalent chromium [Cr (VI)] ions from an aqueous solution. Fourier transform infrared (FT-IR) and energy dispersive X-ray (EDX) spectroscopy characterization results confirmed successful biosynthesis and the presence of elemental silver in the AgNPs. Further, scanning electron microscopy (SEM) and particle size analysis indicated that AgNPs have an amorphous structure and are highly monodispersed. Batch adsorption studies were conducted to investigate the impact of parameters, like pH, time, and initial concentration on Cr (VI) removal efficiency at a fixed AgNP dose of 50 mg and 150 rpm. From the batch study, maximum chromium removal of 87.68% was achieved at an initial concentration of 5 mg/L, pH of 1, and time of 50 min. Results from equilibrium and kinetic study indicated pseudo-second-order reactions kinetics with monolayer coverage. The maximum adsorption capacity of 7.2 mg/g was obtained at an equilibrium time of 50 min and temperature of 30°C. These synthesized AgNPs also displayed significant antibacterial activity against both Gram-positive Bacillus subtilis and Gram-negative Escherichia coli. Based on the results obtained, biosynthesized AgNPs from extracts of A. indica could be utilized for the removal of water pollutants. [ABSTRACT FROM AUTHOR]

The green synthesis of nanoparticles using various plant materials expands the horizons of phytochemists while discouraging the use of toxic chemicals. In this paper, we present a low-cost and environmentally friendly method for producing silver nanoparticles (AgNPs) by using Alhagi persarum flowers (APF) extracts as both a reducing and capping agent for the first time. The bioactive compounds in the extract were characterized using UHPLC-DAD-QqQ-MS/MS, leading to the identification of 18 compounds, including flavonoids, phenolic acids, and alkaloids, with a total phenolic content of 12.17±0.16 mg GAE/g and a total flavonoid content of 23.09±0.33 mg RE/g. The surface plasmon resonance band in UV-vis spectroscopy was used to determine the formation of silver nanoparticles (AgNPs) in the reaction mixture. Fourier transmission infrared (FT-IR) spectroscopy was used to identify the active biomolecules responsible for the reduction and the stabilization of AgNPs synthesized in APF extract. The crystalline structure of metallic silver ions and the presence of pure elemental silver ions were revealed by X-ray diffraction (XRD) and EDX analysis, respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to determine the morphology and topography of the AgNPs. Additionally, the synthesized AgNPs were found to have antimicrobial activity against multidrug-resistant Gram-positive (Staphylococcus aureus), Gram-negative (Escherichia coli and Pseudomonas aeruginosa), and fungus (Candida albicans) clinically isolated human pathogens. Furthermore, the AgNPs were tested for antioxidant activity (DPPH and SO) and cytotoxicity on human breast adenosarcoma cells (MCF-7). Taken together, these results suggest that biosynthesized AgNPs could be used as a potential therapeutic formulation for bacterial infections and breast cancer. [ABSTRACT FROM AUTHOR]

Leishmaniasis, classified as a neglected tropical disease (NTD), is a parasitic infection caused by protozoa and transmitted through vectors. It is a widespread condition found in over 100 countries, known for its destructive nature. Consequently, there is an increasing need to establish novel approaches for combating leishmaniasis and developing effective strategies to combat the disease. In this study, we report an eco-friendly, cost-effective, and biocompatible process for the preparation of silver nanoparticles (AgNPs) using aqueous extract of Crocus sativus petals and their antibacterial and anti-leishmanial activities. Characterization of biosynthesized AgNPs was conducted by UV-vis spectroscopy, TEM, FTIR, DLS, and FESEM spectroscopy. TEM and FESEM images revealed the existence of spherical/oval morphology with a size range of 30–70 nm. Additionally, functional groups associated with the extract were observed, indicating their involvement in the stabilization and coating of the biologically fabricated AgNPs. Furthermore, the AgNPs were confirmed through the observation of a surface plasmon response (SPR) with a peak wavelength of approximately 423 nm. This was accompanied by noticeable color transformation from transparent to brown, providing further evidence of the successful formation of AgNPs. Biosynthesized AgNPs from saffron wastages showed promising anti-leishmanial and antibacterial activities. The AgNPs displayed a zone of inhibition of 23 mm against Staphylococcus aureus and 10 mm against Pseudomonas aeruginosa, indicating their potential antibacterial performance against these microorganisms. The application of an ointment containing quercetin/saffron-capped silver nanoparticles on mice infected with Leishmania major resulted in promising outcomes. The treated group exhibited a reduction in inflammatory responses and an increase in fibroblast activity compared to the untreated group. These results indicate the potential of this compound to alleviate inflammation and promote the growth of fibroblasts, which are beneficial for wound healing and tissue repair. In conclusion, the utilization of biogenically synthesized silver nanoparticles derived from saffron holds promise as an alternative therapeutic approach for treating cutaneous leishmaniasis. [ABSTRACT FROM AUTHOR]

Silver nanoparticles have recently gained significant attention due to their remarkable properties as photocatalysts and antimicrobial agents. However, their widespread use has been hampered by several issues such as aggregation and stabilization. To address these challenges, this study explores the incorporation of silver nanoparticles within potassium polyacrylate (PPA) hydrogel. The integration process was accomplished through in-situ reduction of silver ions using sodium borohydride. The synthesized PPA/Ag nanocomposite was characterized by using UV–visible, XRD, SEM, and FTIR techniques. The silver nitrate (AgNO3) sample had an indirect optical bandgap of 3.3 eV, but adding PPA decreased it to 2.42 eV. The prepared PPA/Ag composites exhibited superior photocatalytic activity in the degradation of rose bengal dye. The highest degradation efficiency of 95% was observed for PPA/Ag (16 mM), while the lowest efficiency of 88% was recorded for PPA/Ag (10 mM). To assess the antibacterial effectiveness of the four PPA/Ag samples (2 mM, 5 mM, 10 mM, and 16 mM) against various bacteria such as E. coli, P. aeruginosa, and S. aureus, the agar diffusion technique was employed. The results show that the largest inhibition zones were achieved in the presence of PPA/Ag (2 mM) samples against E. coli and P. aeruginosa bacterial strains, while PPA/Ag (10 mM) presented a better effect against S. aureus than the other prepared samples. Additionally, the prepared samples demonstrated excellent antimicrobial properties against diverse microorganisms. This finding makes PPA/Ag potentially useful in applications such as wastewater treatment and wound healing. [ABSTRACT FROM AUTHOR]

The research and development of green techniques for the synthesis of silver nanoparticles (AgNPs) with bioactive plants has gained more attention against toxic chemicals. In this research, the aqueous solution of safflower extract was utilized for the simple, green, and commercial synthesis of AgNPs from AgNO3 solution on the wool yarn. The effect of the amount of extract and AgNO3 on the properties of produced nanoparticles was studied. The analysis of AgNPs by Dynamic Light Scattering (DLS) system and Ultravioletvisible (UV-Vis) spectroscopy exhibited that the particle size of produced NPs was <57 nm. In addition, the colorimetric data of wool yarn dyed with safflower extract in the presence of different concentrations of AgNO3 solution were also studied. The results showed that the presence of nanoparticles changed the color hue (hᵒ: 86→58), and the absorption of safflower extract on the wool samples increased from 5 to 29. Also, the ratings of washing and rubbing fastness of dyed samples were satisfactory (4-5). [ABSTRACT FROM AUTHOR]

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Doxorubicin (DOX) is the most used chemotherapeutic agent for treating solid tumors. DOX treatment may lead to testicular damage using oxidative stress, resulting in infertility. These adverse effects may be prevented by the activation of antioxidant systems. Oleuropein (OLE) is a powerful flavonoid with several ameliorative effects, including antioxidative, antiproliferative, and anti-inflammatory. It would be more efficient and applicable in treating chronic human diseases if its poor bioavailability improves with a nano-delivery system. The current study aims to assess the histopathological changes and antioxidative effects of OLE loaded with silver nanoparticles oleuropein (OLE-AgNP) on the testicular injury triggered by DOX in rats. Forty-eight male albino rats were randomly divided into six groups as follows: the control, DOX (2.5 mg/kg), OLE (50 mg/kg), AgNP (100 mg/kg), OLE + AgNP (50 mg/kg), OLE (50 mg/kg) + DOX (2.5 mg/kg), AgNP (100 mg/kg) + DOX (2.5 mg/kg), and OLE-AgNP (50 mg/kg) + DOX (2.5 mg/kg) for 11 days. Oxidative stress, inflammation, apoptosis, endoplasmic reticulum stress markers, sperm analysis, and histopathological analyses were performed on testicular tissues taken from rats decapitated after the applications and compared between the experimental groups. The tissue MDA level was lower in the OLE and OLE+AgNP-treated groups than in the DOX-treated group. In addition, SOD and GSH levels significantly increased in both the OLE and OLE+AgNP-treated groups compared to the DOX group. Both OLE and OLE+AgNP, particularly OLE+AgNP, ameliorated DOX-induced testicular tissue injury, as evidenced by reduced injury and improved seminiferous tubules and spermatocyte area. In addition, OLE and OLE+AgNP, especially OLE+AgNP, inhibited DOX-induced testicular tissue inflammation, apoptosis, and endoplasmic reticulum stress. The findings suggest that nanotechnology and the production of OLE+AgNP can ameliorate DOX-induced testicular damage. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNP) are the dominant nanomaterials in commercial products and the medical field, but the widespread occurrence of AgNP has become a global threat to human health. Growing studies indicate that AgNP exposure can induce vascular endothelial toxicity by excessive oxidative stress and inflammation, which is closely related to cardiovascular disease (CVD), but the potential intrinsic mechanism remains poorly elucidated. Thus, it has been crucial to control the toxicological effects of AgNP in order to improve their safety and increase the outcome of their applications. Multiple researches have demonstrated that sodium selenite (Se) possesses the capability to counteract the toxicity of AgNP, but the functional role of Se in AgNP-induced CVD is largely unexplored. The aim of this study was to explore the potential protective effect of Se on AgNP-induced vascular endothelial lesion and elucidate the underlying mechanisms. An in vivo model of toxicity in animals was established by the instillation of 200 µL of AgNP into the trachea of rats both with (0.2 mg/kg/day) and without Se treated. In vitro experiments, human umbilical vein endothelial cells (HUVECs) were incubated with AgNP (0.3 µg/mL) and Se for a duration of 24 h. Utilizing transmission electron microscopy, we observed that the internalization of AgNP-induced endothelial cells was desquamated from the internal elastic lamina, the endoplasmic reticulum was dilated, and the medullary vesicle formed. Se treatment reduced the levels of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), inhibited the release of pro-inflammatory cytokines (specifically tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6), improved endothelial cell permeability, integrity, and dysfunction, and prevented damage to the aortic endothelium caused by AgNP. Importantly, we found that Se showed the capacity against AgNP with biological functions in guiding the intracellular reactive oxygen species (ROS) scavenging and meanwhile exhibiting anti-inflammation effects. Se supplementation decreased the intracellular ROS release and suppressed NOD-like receptor protein 3 (NLRP3) and nuclear factor kappa-B (NF-κB) mediated inflammation within AgNP-intoxicated rats and HUVECs. The anti-oxidant stress and anti-inflammatory effects of Se were at least partly dependent on nuclear factor erythroid 2-related factor 2 (Nrf2). Overall, our results indicated that the protectiveness of Se against AgNP-induced vascular endothelial toxicity injury was at least attributed to the inhibition of oxidative ROS and pro-inflammatory NF-κB/NLRP3 inflammasome by activating the Nrf2 and antioxidant enzyme (HO-1) signal pathway. [ABSTRACT FROM AUTHOR]

Silver nanocomposites (Ag-NPs/PVP) were synthesized through the reduction of Ag+ using Ethylene glycol (EG) and poly(N-vinylpyrrolidone) (PVP) as a protective agent in an alkaline medium. Characterization involved UV–Vis spectrum, and TEM image, confirming the well spread of the nanoparticles with a particle size of range 5–10 nm. Stability, assessed after three months, revealed a zeta potentialof −17 mV, identicating no agglomeration.. PVP role in decreasing the nanoparticle size was studied, attributed to the protective layer preventing aggregation.. The study enhanced the antibacterial activity of various cellulosic fabrics (cotton, linen, and viscose) by activating their surfaces through O2 plasma pretreatment at atmospheric pressure. Activation immobilized the fabric matrix by the extracting radicals fforming functional groups(C = O, –O–C = O, –COH, –COOH, and CH2–OH). Viscose demonstrated the highest effect. FTIR confirmed the formation of polar groups on the fabric surface. Activated cellulosic fabric was treated with Ag-NPs/PVP colloid solution and antibacterial activity was assessed against Staphylococcus aureus (S. aureus) andEscherichia coli (E. coli). Parameters such as: plasma exposure time, Ag-NPs/PVP concentration, and the pretreatment bath temperature were studied.SEM images and EDX spectra verified the presence of nitrogen and silver elements on the treated substrates surface. [ABSTRACT FROM AUTHOR]

To achieve precision and selectivity, anticancer compounds and nanoparticles (NPs) can be targeted with affinity ligands that engage with malignancy-associated molecules in the blood vessels. While tumor-penetrating C-end Rule (CendR) peptides hold promise for precision tumor delivery, C-terminally exposed CendR peptides can accumulate undesirably in non-malignant tissues expressing neuropilin-1 (NRP-1), such as the lungs. One example of such promiscuous peptides is PL3 (sequence: AGRGRLVR), a peptide that engages with NRP-1 through its C-terminal CendR element, RLVR. Here, we report the development of PL3 derivatives that bind to NRP-1 only after proteolytic processing by urokinase-type plasminogen activator (uPA), while maintaining binding to the other receptor of the peptide, the C-domain of tenascin-C (TNC-C). Through a rational design approach and screening of a uPA-treated peptide-phage library (PL3 peptide followed by four random amino acids) on the recombinant NRP-1, derivatives of the PL3 peptide capable of binding to NRP-1 only post-uPA processing were successfully identified. In vitro cleavage, binding, and internalization assays, along with in vivo biodistribution studies in orthotopic glioblastoma-bearing mice, confirmed the efficacy of two novel peptides, PL3uCendR (AGRGRLVR↓SAGGSVA) and SKLG (AGRGRLVR↓SKLG), which exhibit uPA-dependent binding to NRP-1, reducing off-target binding to healthy NRP-1-expressing tissues. Our study not only unveils novel uPA-dependent TNC-C targeting CendR peptides but also introduces a broader paradigm and establishes a technology for screening proteolytically activated tumor-penetrating peptides. [ABSTRACT FROM AUTHOR]

Bryophyllum pinnatum is used to cure infections worldwide. Although the flavonoids of this plant are well known, it is still unknown how much of the plant’s Ag and ZnO nanoparticles are beneficial. In the current research work, silver and zinc oxide nanoparticles were prepared using Bryophyllum pinnatum extract. The synthesized particles were characterized by UV-visible spectroscopy, SEM, EDS, XRD and FTIR. Synthesized particles were subjected to evaluation of their bactericidal and antifungal activity at various doses. Uv vis spectra at 400 nm corresponding to AgNPs confirmed their synthesis. Strong peaks in the EDS spectra of Ag and ZnO indicate the purity of the sample. The scanning electron microscopic images of ZnONPs showed a size of about 60 nm ± 3 nm, which demonstrated the presence of triangular-shaped ZnO nanoparticles. Green synthesized nanoparticles showed bactericidal activity against both Gram-positive (Micrococcus luteus, Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Agrobacterium tumifaciens, Salmonella setubal, Enterobacter aerogenes) strains. AgNPs proved to be more effective against Gram-negative bacterial strains compared to Gram-positive owing to MIC values (10 ppm and 20 ppm respectively). Whereas, ZnONPs were found more effective against Gram-positive bacteria with lower MIC values (10 ppm) as compared to Gram-negative ones (20 ppm). Also, the synthesized nanoparticles exhibited moderate dose-dependent antifungal activity against tested fungal strains ranging from 10 to 70%. Cytotoxicity of nanoparticles was found significant using Brine shrimp’s lethality assay with IC50 values of 4.09 ppm for AgNPs, 13.72 ppm for ZnONPs, and 24.83 ppm for plant extract. Conclusively, Ag and ZnO nanoparticles were more effective than plant extract and AgNPs had higher activities than those of ZnONPs. Further research is warranted to explore the precise mechanism of action and the potential applications of these nanoparticles in the medical field. [ABSTRACT FROM AUTHOR]

AbstractCompared with conventional solders, nano-silver benefits low-temperature sintering and high-temperature service, perfectly matching the high-temperature operating environment for third-generation semiconductor devices. However, the synthetic cost, complexity of the sintering process and the low connection strength limit its development. This paper describes the physical, chemical reduction and biological methods of synthesizing and compares the advantages and disadvantages of these three methods. The process parameters affecting the sintering process of silver nanoparticles (Ag NPs) are presented in a comprehensive and in-depth manner. Present methods are also introduced to improve the quality of nano-silver joints, such as the adding enhancement, the silver nanostructured films, and a trimodal-Ag paste consisting of silver particles in three sizes: nano, submicron and micron, aiming to break the limitation of the poor quality of nano-silver joints. In addition, this paper provides the first comprehensive summary of the sintering process and sintering mechanism of nano-silver, and introduces the latest results of the study of the sintering mechanism of nano-silver by using the Molecular Dynamics Simulation (MDS) technique. At the end, the advanced applications of nano-silver are shown, thus pointing out the direction for the further development and applications of nano-silver. [ABSTRACT FROM AUTHOR]

Orange (Citrus sinensis L.) is a common fruit crop widely distributed worldwide with the peel of its fruits representing about 50% of fruit mass. In the current study, orange peel was employed to mediate the synthesis of silver nanoparticles (AgNPs) in a low-cost green approach. Aqueous extracts of suitably-processed peel were prepared using different extraction methods; and their phytochemical profile was identified. Based on phytochemical screening, amount of main phytochemicals, free radical-scavenging ability, reducing power and antioxidant activity, the peel extract prepared by boiling seemed to be the most promising. Thus, major compounds of this extract were identified by gas chromatography-mass spectrometry. Potency of the peel extract to mediate the synthesis of AgNPs was then monitored by visual observation, UV-visible spectroscopy, energy dispersive X-ray analysis, transmission electron microscopy and zetametry. Color change of the reaction mixture to brown and absorption peak at 450 nm indicated AgNPs formation. Characterization of AgNPs revealed spherical shape, size of 30–40 nm, zeta potential of -18.2 mV and yield conversion of 82%. The as-synthesized AgNPs had antioxidant capacity (free radical-scavenging ability, reducing power and antioxidant activity) lower than that of the orange peel extract. However, these biogenic AgNPs had antitumor activity (IC50 of 16 ppm against HCT-116 and 1.6 ppm against HepG2 cell lines) much higher than the peel extract that was completely non-toxic to the considered cell lines. [ABSTRACT FROM AUTHOR]

Traditional antibiotics have specific intracellular targets and disinfect in chemical ways, and multi-drug resistance induced by antibiotics has become an emerging threat to human health. Therefore, it is urgent to develop novel antibacterial agents to combat multi-drug resistance. Herein, we report a new antibacterial nanocomposite (PGH@AgNPs), which was prepared by decorating polymeric guanidine hydrochloride with silver nanoparticles (AgNPs). The Ce(IV)/pentaerythritol redox system was used to initiate the polymerization of a vinyl monomer, guanidine hydrochloride (GH), to prepare star-shaped polymerized GH (PGH), which was then decorated with silver nanoparticles (AgNPs). The physicochemical properties of the nanocomposite were characterized using UV, SEM, XPS and XRD. The biological assays revealed that the nanocomposite possessed effective broad-spectrum antibacterial properties, showing the minimum inhibitory concentrations (MICs) ranging from 6 to 12 µg mL−1, a sterilization rate of higher than 90%, and MIC values of 8, 12 and 12 µg mL−1 against the clinically isolated drug-resistant bacteria MRSA (TACC43300), VRE and P. aeruginosa, respectively. Particularly, S. aureus and P. aeruginosa treated with PGH@AgNPs did not develop drug resistance even after 21 passages because PGH@AgNPs could irreversibly damage the bacterial membrane structure and induce the generation of reactive oxygen species (ROS), ultimately killing the bacteria. In addition, PGH@AgNPs exhibited high blood biocompatibility in mouse fibroblast cells (L929). Overall, PGH@AgNPs has great potential to be used as an antibacterial material with high cytocompatibility for the control of multi-drug-resistant bacterial infections. [ABSTRACT FROM AUTHOR]

Herein, silver phosphate nanoparticles decorated with melamine–formaldehyde polymer nanocomposite (Ag3PO4-MFP) were fabricated. The synthesized nanocomposite was assessed for the catalytic reduction of mono, di, and tri-nitrophenols, such as p-nitrophenol (PNP), di-nitrophenol (DNP), and tri-nitrophenol (TNP), to their corresponding aminophenols (APs) using NaBH4 in an aqueous medium, particularly at ambient conditions. The % reduction of PNP, DNP, and TNP was ∼99%, ∼96%, and ∼63%, respectively. [ABSTRACT FROM AUTHOR]

The development of electrodes for hydrogen evolution via water splitting in a neutral electrolyte is highly desirable, especially considering that natural water resources such as seawater typically have a neutral pH. In this study, silicon nanowires (SiNWs) arrays with uniform silver (Ag) decoration are prepared as a cathode material, which exhibits excellent and stable electrochemical performance for neutral water electrolysis. Ag ions, utilized in the preparation of SiNWs through metal-assisted chemical etching technique, are retained and decorated within the SiNWs array without undergoing a dissolution process, referred to as Native SiNWs. Remained Ag+ ions on the SiNWs are activated photocathodically and reduced to Ag0, resulting in a significantly enhanced performance as an electrocatalyst for hydrogen evolution reaction (HER). Hence, this photocathodic activation of Native SiNWs (PCA-Native SiNWs) eliminates the need for additional cocatalyst deposition for HER, utilizing the Ag ions employed in the SiNWs preparation process. This enhancement in HER activity is exclusively observed by photocathodic activation, not by cathodic activation without light irradiation, indicating the crucial role of photoelectrons in SiNWs under light irradiation for the activation. Additionally, the nanowire structure serves as an ideal platform for Ag nanoparticles, providing sufficient surface area, resulting in excellent dispersion and an increased number of active sites. Furthermore, PCA-Native SiNWs demonstrates outstanding electrochemical stability for over 60 h, with no significant reduction in current density or structural degradation in a neutral electrolyte. Several characterizations and electrochemical analyses have been conducted to elucidate the in-situ decoration of Ag nanoparticles on SiNWs and investigate the surface chemistry for the activation mechanism. This work introduces a new perspective on using Ag-decorated SiNWs directly as an electrocatalyst for effective hydrogen evolution in a neutral media. Saleem et al., "A Strategy to Reutilize Silver Nanoparticles on Silicon Nanowires via Photocathodic Activation for Enhanced and Sustainable Hydrogen Evolution"Native SiNWs, which are prepared by retaining Ag nanoparticles during SiNW synthesis, exhibited better performance for HER than SiNWs. Additionally, the retained Ag can be more evenly distributed and reduced during photocathodic activation, resulting in significantly improved HER activity. [Display omitted] • Photocathodically activated Native SiNWs (PCA-Native SiNWs) are developed. • Retained Ag ions on SiNWs are reduced and activated by light irradiation and cathodic potential (photocathodic activation). • Reduced Ag enhances electrochemical performance of SiNWs as an electrocatalyst. • Ag nanoparticles are evenly distributed vis the dissolution-redeposition phenomenon. • PCA-Native SiNWs show stable activity in neutral pH. [ABSTRACT FROM AUTHOR]

Osteoporosis (OP) is a chronic disease characterized by diminished bone mass and structural deterioration, ultimately leading to compromised bone strength and an increased risk of fractures. Diagnosis primarily relies on medical imaging findings and clinical symptoms. This study aims to explore an adjunctive diagnostic technique for OP based on surface-enhanced Raman scattering (SERS). Serum SERS spectra from the normal, low bone density, and osteoporosis groups were analyzed to discern OP-related expression profiles. This study utilized partial least squares (PLS) and support vector machine (SVM) algorithms to establish an OP diagnostic model. The combination of Raman peak assignments and spectral difference analysis reflected biochemical changes associated with OP, including amino acids, carbohydrates, and collagen. Using the PLS-SVM approach, sensitivity, specificity, and accuracy for screening OP were determined to be 77.78%, 100%, and 88.24%, respectively. This study demonstrates the substantial potential of SERS as an adjunctive diagnostic technology for OP. [ABSTRACT FROM AUTHOR]

This systematic review investigates the antibacterial effects of silver nanoparticles (AgNPs) on polymicrobial biofilms in endodontics, emphasizing their potential enhancement of traditional treatment methods. Recognizing the limitations of current endodontic disinfectants in fully eradicating complex biofilms, this study focuses on the synergistic potential of AgNPs to improve antimicrobial efficacy. Utilizing a systematic approach based on PRISMA guidelines, the review draws on studies from databases like PubMed, Web of Science, and SCOPUS up to 2024. The included research specifically examines the role of AgNPs in various endodontic applications against resilient biofilms, adhering to strict inclusion criteria that demand clear methodology and measurable outcomes. The results suggest that AgNPs can significantly augment the biofilm disruption capabilities of conventional antimicrobials, potentially due to their ability to modify the biofilm matrix and enhance agent penetration. However, the effectiveness varies depending on the nanoparticle concentration and application technique, indicating a need for further optimized studies. In conclusion, while AgNPs show promise in enhancing endodontic antimicrobial protocols, additional in vivo research is necessary to establish standardized, effective, and safe clinical applications. The review highlights the complex interactions between nanoparticle properties and biofilm biology, underscoring the importance of further investigation in this area. [ABSTRACT FROM AUTHOR]

For utilizing biodegradable waste as a natural source for nanofabrication, this study was designed to highlight a simple, sustainable, safe, environmentally friendly, and energy consumption reduction waste management approach using hot aqueous extract of Punica granatum (pomegranate) peel waste (PPE) to biosynthesize silver nanoparticles (PPE‐AgNPs). The fabrication of biosynthesized nanosilver was confirmed by UV–visible spectroscopy, scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX), X‐ray diffraction (XRD), and atomic force microscope (AFM). The initial pale brown color change upon adding silver nitrate to PPE confirmed bioreduction. For PPE, the absorption spectrum for UV–vis spectroscopy in the visible light region was 230–290 nm, while for PPE‐AgNPs, the graph shows that surface plasmon resonance (SPR) spectrum for nanosilver at 360–460 nm. The XRD analysis proved that the PPE‐AgNPs were crystalline in nature. The SEM micrograph revealed that silver nanoparticles were sphere‐shaped, homogenous accumulations with particle size in the range of 21.63–30.97 ± 0.4 nm. The EDX data analysis also proved the presence of a sharp peak of silver element with 8.83% weight at 3 keV. The 3D AFM images of Ag nanoparticles illustrated that the diameter is around 7.20–14.80 nm with a median of 7.16 ± 1.3 nm and the root mean square (RMS) value corresponds to 1.40 ± 0.4 nm. The PPE‐AgNPs efficiently exhibited a potent antioxidant and dose‐dependent DPPH inhibition action. Visual and microscopic observations of fresh human blood when treated with 25, 50, 75, and 100 μg/mL of PPE‐AgNPs were proven to be biocompatible with no morphological changes and no coagulation. This study predicts that PPE can be utilized to synthesize biocompatible nanosilver. [ABSTRACT FROM AUTHOR]

In view of the increasing bacterial resistance, 2D MXenes are promising alternatives to antibiotics. However, MXene-based photothermal therapy (PTT) suffers from unsatisfactory antibacterial efficiency and heat-resistant strains. Here, we prepared a Ti3C2 MXene and Ag hybridized antibacterial nanocomposite [MXene/metal-polyphenol networks (MPNs)/Ag] through the in situ reduction of Ag nanoparticles on MPN wrapped MXene matrix. The use of MPNs as the reducing agents of Ag+ and anchoring agents of Ag nanoparticles endowed MXene/MPN/Ag with a tight immobilization capacity and improved colloidal dispersion stability of Ag nanoparticles. The pH-triggered decomposition of MPNs led to the pH-responsive release of Ag to achieve combined MXene-based PTT and Ag-mediated therapy for enhanced antibacterial efficiency. In vitro antibacterial experiments revealed its satisfactory bactericidal activities against both planktonic bacteria and bacteria in stubborn biofilms. In vivo antibacterial assays solidly confirmed its high antibacterial therapeutic efficiency, strong anti-inflammatory ability, and good biosafety. Therefore, the in situ combination of Ag nanoparticles with MXenes offers a promising microenvironment-responsive 2D bactericidal candidate for infection that could be applied in future antibacterial treatments. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) by biological synthesis have many advantages. Among them, herbs attract wide attention due to their unique medicinal effects. In this paper, the water/alcohol/ether extracts of dried or fresh Artemisia annua were used as reducing agents and stabilizers to synthesize AgNPs. Water is a highly polar solvent that can effectively extract polar compounds such as phenolic profile, which possesses strong reducing properties and enables the reduction of Ag+ to AgNPs. The prepared AgNPs were characterized using ultraviolet–visible (UV–vis) absorption spectra, X‐ray diffraction (XRD), Fourier transform infrared (FT‐IR) spectroscopy, transmission electron microscopy (TEM), and zeta potential analysis. The AgNPs prepared from the water extracts of dried Artemisia annua have obvious bacteriostatic effects on six common aquatic pathogens and have a wide application prospect in aquaculture. The inhibition zone against Vibrio anguillarum is up to 16.88 mm. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Vibrio anguillarum are 1.09 µg/mL and 2.17 µg/mL, respectively, which is lower than most published reports. [ABSTRACT FROM AUTHOR]

This is the primary study at Matrouh Governorate to unveil antibiotic resistance, biofilm formation, silver nanoparticles (Ag-NPs) effect using electron microscopy, and REP-PCR analysis of Staphylococcus aureus strains isolated from COVID-19 patients, contaminated food, and Morel's diseased sheep and goats. A total of 15 S. aureus strains were isolated; five from each of the COVID-19 patients, Morel's diseased sheep and goats, and contaminated food. All strains were considered multidrug-resistant (MDR). All strains showed the presence of biofilm. Morphological changes in the cell surface of the bacterium were evidenced, and penetration with the rupture of some bacterial cells. Based on REP-PCR analysis, 4 clusters (C1-C4) with dissimilarity between clusters C1 and C2 8% and between C3 and C4 15%. Cluster I included 3 strains from contaminated food with a similarity of 97%, and Cluster II included 2 strains from contaminated food and 2 from COVID-19-infected patients with a similarity of 96% (confirming the zoonotic nature of this pathogen). Cluster III contained 4 strains isolated from Morel's diseased sheep & goats with a similarity ratio of 99% in comparison the 4th cluster contained 3 strains isolated from COVID-patients and one from Morel's diseased sheep & goats with a similarity ratio of 92%. [ABSTRACT FROM AUTHOR]

Dopamine (DA) is a potent neuromodulator in the brain that affects a wide range of motivated behaviors. Abnormal concentration of DA is related to a variety of diseases. Hence, it is imperative to establish a rapid and precise method for quantifying DA. In this work, we integrate orange-yellow emissive carbon dots (CDs) with target-induced silver deposition on gold nanoparticles (Au NPs), forming gold/silver core-shell nanoparticles (Au@Ag NPs), to construct a fluorometric and colorimetric dual-signal sensor for sensitive detection of DA. Au NPs and silver ions (Ag+) have minimal effect on the fluorescence of CDs. DA can reduce the silver ions to Ag(0) on the surface of the Au NPs to form a silver shell, resulting in the blue-shift of the absorbance peak from 520 to 416 nm, which overlaps with the excitation spectrum of CDs. As a result, the system color turns from pink to orange-yellow, and the fluorescence of CDs is quenched due to the strong inner filter effect. The linear range of the colorimetry is 0.5–18 μM with a limit of detection (LOD) of 0.41 μM, while the linear range for the fluorometry method is 0.5–14 μM with a LOD of 0.021 μM. This method demonstrates notable advantages including a low detection limit, rapid response time, and straightforward operation in practical samples, showing great potential in biomedical analysis. [ABSTRACT FROM AUTHOR]

Acinetobacter baumannii, an opportunistic pathogen has shown an upsurge in its multi-drug resistant isolates. OmpA of A. baumannii induces incomplete autophagy and apoptosis in host cells. Various therapeutic alternatives are under investigation against A. baumannii. Here, the major emphasis has been laid on comparing the efficacy of AgNP with different capping agents. OmpA targeted lead, Ivermectin capped AgNP (IVM-AgNP) has been compared with the antibacterial polyvinylpyrrolidone capped AgNP (PVP-AgNP) for their role in the modulations of host autophagy. Upregulation of p62 and LC3B confirmed by real-time PCR analysis indicated an increased autophagic flux upon the treatment with AgNPs. The elongation and closure of autophagic vacuoles was also supported by upregulated Atg genes (Atg4, Atg3, Atg5) in A. baumannii infected cells after treatment with AgNP. Autophagic flux increased on treatment with PVP-AgNP as suggested by the rise in mcherryLC3B fluorescence in A549 cells treated with PVP-AgNP as compared to the GFP-LC3B of IVM-AgNP. This suggests that PVP-AgNP treatment more effectively promotes the elongation and maturation stages of autophagy by increasing autophagic flux. These results indicate that capped AgNPs have the efficiency to revert the incomplete autophagy induced by A. baumannii back to normal autophagic levels. [ABSTRACT FROM AUTHOR]

The present study was aimed to synthesize the silver nanoparticles from Alangium salvifolium Wang. and evaluating its biomedical applications. The leaves of A. salvifolium collected and subjected for the standard procedure of Soxhlet extraction using distilled water as a solvent. With the help of an aqueous extract AgNPs were synthesized from silver nitrate using phyto-reduction method. Further, synthesized AgNPs were characterized using several analytical techniques such as UV, FTIR, SEM–EDX, XRD, particles size and zeta potential. Synthesized AgNPs were tested for antibacterial, antioxidant, anticancer for lung cancer cell line and flowcytometry-based pathway studies. The visual observation confirmed the formation of AgNPs from the aqueous extract by changing yellow to brown colour formation. Further, characterization techniques also confirmed the formation of AgNPs. Antibacterial activity results showed that the tested AgNPs were potent against bacterial pathogens with a higher zone of inhibition. Further, the antioxidant and anticancer activity of AgNPs revealed that the AgNPs have exhibited significant results with a good percentage of inhibition. Further, the flow cytometry studies confirmed that the AgNPs inducing apoptosis and cell cycle arrest in lung cancer. The phytochemicals of A. salvifolium plant have successfully synthesized AgNPs. In the case of performed biological activity, the synthesized silver nanoparticles exhibited potent activity. In future these AgNPs can be taken for molecular and in vivo studies to identify their efficacy using in vivo and molecular models. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis of silver nanoparticles (AgNPs) using the extract of Aphania senegalensis leaves. The extraction was done using maceration at room temperature in water for 48 h. The synthesized nanoparticles were characterized by IR, XRD, TEM, and SEM. The thermal stability of these nanoparticles was studied by TGA. The zeta potential was used to define the size, charge distribution, and stability of the nanoparticles. Optimization reactions were carried out based on reaction time, pH, and temperature. The nanoparticles obtained from optimal conditions were evaluated on induced inflammation. The determination of the average diameters and geometry of nanoparticles was carried out by XRD by calculating the lattice constants, and they are between 18.11 and 50 nm. The evaluation of anti‐inflammatory activity showed that the nanoparticles are 10 times more active than the extract of Aphania senegalensis leaves. Minimum doses of 10 mg/kg orally and 3 mg/kg were obtained for the plant extract, respectively. These results are promising for the possibility of AgNPs to be used for the treatment of inflammation. [ABSTRACT FROM AUTHOR]

The presence of pharmaceuticals in water bodies has been reported to be mainly due to their incomplete removal by the conventional wastewater treatment processes, resulting to their release into the aquatic environment where they thratens to human health and aquatic life. Therefore, it is important to remove these pollutants from the aquatic environment using affordable highly efficient materials. The goal of this study was to incorporate silver nanoparticles (AgNPs) into MIPs for selective removal of sulfamethoxazole, nevirapine, and ibuprofen in wastewater. The AgNPs were synthesized using starch (St) and macadamia (MCD) as both reducing and stabilizing agents. Thermogravimetric analysis showed high stability for the St/MCD‐nanoMIPs. The ANOVA analysis revealed that the parameters affecting adsorption of St/MCD‐nanoMIPs have a significant difference (p<0.05). The St/MCD‐AgNPs experimental data fitted to both Langmuir and Freundlich adsorption isotherms, however, the non‐linear Langmuir isotherm model yielded a better fit based on the higher R2 value (0.999). The non‐linear Freundlich model best fitted for the St/MCD‐nanoMIPs. The linear pseudo‐second order model shown best fit for St/MCD‐nanoMIPs, the thermodynamic results revealed that the adsorption process was spontaneous and endothermic. The St/MCD‐nanoMIPs showed improved qualities and were highly selective (>70 %) and effective in removing the selected pharmaceuticals from wastewater. [ABSTRACT FROM AUTHOR]

By combining mechanical treatment of aluminium alloy with subsequent surface modification using micro-arc oxidation (MAO) technology, zinc oxide (ZnO) oxide coatings were prepared, which achieved enhanced hydrophobic properties, excellent antibacterial activity and corrosion resistance. The coatings were oxidised at different MAO discharge intensities using different frequencies. All surfaces were subjected to determination of wettability, corrosion resistance and chemical stability at 1, 7, 14, and 28 days and antibacterial activity of the coatings against the bacterial population of Staphylococcus aureus, Escherichia coli with an evaluation of population inhibition after 24 h. The surfaces mechanically modified by blasting showed a hydrophobic character; their subsequent oxidation by MAO contributed to a significant increase in hydrophobic properties. The sample with the highest Zn content (1.1 wt%), prepared at an MAO source frequency of 222 Hz, i.e. at the most intense plasma discharge, showed the most significant chemical stability in simulated body fluid (SBF) and distilled water and showed the highest antibacterial activity after 24 h. Thus, blasting of aluminium alloy surfaces and their subsequent MAO in alkaline electrolyte allows to obtain oxide coatings with antibacterial, hydrophobic and corrosion-resistant properties with the possibility of their use on surfaces with potential occurrence of harmful bacteria. • Oxide layers on aluminium alloy were prepared in alkaline electrolyte. • Frequencies of 49, 95 and 222 Hz, blasting and MAO technology combination were used. • Mechanically modified layers and MAO coatings achieved hydrophobic properties. • ZnO-doped MAO coatings had antibacterial properties and higher corrosion resistance. [ABSTRACT FROM AUTHOR]