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ZnO/g-C3N4 heterojunction modified with Ag nanoparticles (ZnO/CN/Ag) was synthesized by depositing ZnO nanorods/Ag nanoparticles onto g-C3N4 nanosheets. Under xenon lamp irradiation, 99% of Rhodamine B (RhB) was degraded by ZnO/CN/Ag-5% composite within 30 min, which was much higher than the degradation efficiency of ZnO and ZnO/CN. The synergistic effect of g-C3N4 and ZnO, along with the localized surface plasmon resonance effect of Ag NPs, contributes to the improvement of photocatalytic performance. Ag nanoparticle provides another charge transfer path from g-C3N4 to ZnO, which speeds up the separation of electron–hole pairs. Meanwhile, the catalyst had good stability and recyclability. Finite-difference time-domain method and the density functional theory were used to obtain the charge transfer process. The photodegradation process has been studied in depth. [ABSTRACT FROM AUTHOR]

Due to their high similarity to biological ion channels, low power consumption, small footprint, and the fact that they do not require reset circuits, threshold switching memristors have been intensively studied for simulating neurons in neuromorphic chips. Switching speed is one of the key challenges which limit the application of threshold switching memristors in chips. In this study, Ta2O5 threshold switching memristors with high switching speeds were prepared by doping with silver. The results show that 14 wt. % Ag doped Ta2O5 threshold switching memristors exhibit excellent bi-directional threshold switching performance, featuring fast switching speeds (<20 ns, <18 ns), low leakage currents (<10 pA), and high switching ratio (>107). According to the field nucleation theory, the rapid switching speed can be attributed to the low nucleation energy (0.26 eV) of silver within the Ta2O5 matrix, which is achieved by incorporating 14 wt. % Ag during the doping process. Based on Pspice, a LIF (leaky integrate-and-fire) neuron based on the silver nanoparticles doped Ta2O5 threshold switching memristors is built, and its firing function has been simulated. The results show that the LIF neuron with a short switching time is able to excite pulse spiking with high frequencies. These results demonstrated that the silver nanoparticles doped Ta2O5-based threshold switching memristors hold significant potential for constructing high-speed artificial neural networks. [ABSTRACT FROM AUTHOR]

Grafting nanomaterials on the carbon fiber (CF) surface is considered an effective strategy for enhancing the interfacial properties of CF-reinforced polymer composites (CFRPs). However, the mechanical properties of the CFs are often compromised during treatment. A new method for in situ growing silver nanoparticles (AgNPs) on the CF surface is proposed in this study. The CFs are first immersed in a low-viscosity silver nitrate solution to form a thin liquid film on the surface. Subsequently, using the abundant active particles in the plasma, the silver ions are reduced to silver atoms and grown into AgNPs on the CF surface. The tensile strength of CF@Ag was 38.74% greater than that of untreated CF, potentially due to the reparative action of AgNPs on defects in CF. The CF showed an evident improvement in surface wettability because of the AgNPs. Furthermore, the interfacial properties were noticeably improved, with the interfacial shear strength of CF@Ag increasing to 91.59 MPa, which was about twice that of pristine CF. Thus, the mechanical properties of composites are significantly improved (flexural strength increased by 190.74%). This study presents a non-destructive and convenient method for growing nanoparticles onto CF to establish a robust interface in CFRPs. [ABSTRACT FROM AUTHOR]

A combination of experimental and numerical investigations on metallic silver and platinum nanoparticles deposited on silica substrates is presented, with a focus on metal–substrate interactions. Experimentally, the nanoparticles, obtained by ultra-high vacuum atom deposition, are characterized by grazing-incidence small-angle x-ray scattering and high resolution transmission electronic microscopy to determine their structure and morphology and, in particular, their aspect ratio (height/diameter), which quantifies the metal–substrate interaction, from the as-grown to equilibrium state. Numerically, the interactions between the metal and the silica species are modeled with the Lennard-Jones (12, 6) potential, with two parameters for each metal and silica species. The geometric parameters were found in the literature, while the energetic parameters were determined from our experimental measurements of the aspect ratio. The parameters are as follows: σAg–O = 0.278 nm, σAg–Si = 0.329 nm, ɛAg–O = 75 meV, and ɛAg–Si = 13 meV for Ag–silica and σPt–O = 0.273 nm, σPt–Si = 0.324 nm, ɛPt–O = 110 meV, and ɛPt–Si = 18 meV for Pt–silica. The proposed Ag–silica potential reproduces quantitatively the unexpected experimental observation of the variation of the aspect ratio for Ag nanoparticles larger than 5 nm, which has been interpreted as a consequence of the silica roughness. The nanoparticle orientation, structure, and disorder are also considered. This metal–silica potential for Ag and Pt should be helpful for further studies on pure metals as well as their alloys. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the biocompatibility of silver nanoparticle (AgNP)-doped Ti-6Al-4V surfaces by evaluating the viability and proliferation rate of human gingival fibroblasts (HGFs)--as the dominant cells of peri-implant soft tissues-- seeded on the modified surfaces. Materials and Methods: AgNPs (sizes 8 nm and 30 nm) were incorporated onto Ti-6Al-4V specimen surfaces via electrochemical deposition, using colloid silver dispersions with increasing AgNP concentrations of 100 ppm, 200 ppm, and 300 ppm. One control and six experimental groups were included in the study: (1) control (Ti-6Al- 4V), (2) 8 nm/100 ppm, (3) 8 nm/200 ppm, (4) 8 nm/300 ppm, (5) 30 nm/100 ppm, (6) 30 nm/200 ppm, and (7) 30 nm/300 ppm. HGF cell primary cultures were isolated from periodontally healthy donor patients and cultured in direct contact with the group specimens for 24 and 72 hours. The cytotoxicity of AgNP-doped Ti-6Al-4V specimens toward HGF was assessed by the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) and BrdU (5-bromo-2'-deoxyuridine) assay tests. Calcein AM and ethidium homodimer (EthD-1) fluorescent stains were used to determine the live and dead cells. The morphology and attachment properties of the HGFs were determined via scanning electron microscopy (SEM). Results: Energy dispersive x-ray (EDX) analysis confirmed the presence of AgNPs on the specimens. The MTT test revealed that AgNPs of both sizes and all concentrations presented a decreased cellular metabolic activity compared to the control discs. All concentrations of both sizes of AgNPs affected the cell proliferation rate compared to the control group, as revealed by the BrdU assay. Overall, cytotoxicity of the modified Ti-6Al-4V surfaces depended on cell exposure time. Observation via confocal microscopy confirmed the results of the MTT and BrdU assay tests. Specifically, most cells remained alive throughout the 72-hour culture period. SEM images revealed that adjacent cells form bonds with each other, creating confluent layers of conjugated cells. Conclusions: The findings of the present study indicate that Ti-6Al-4V surfaces modified with 8 nm and 30 nm AgNPs at concentrations of 100 ppm, 200 ppm, and 300 ppm do not produce any serious cytotoxicity toward HGFs. The initial arrest of the HGF proliferation rate recovered at 72 hours. These results on the antibacterial activity against common periodontal pathogens, in combination with the results found in a previous study by the same research group, suggest that AgNP-doped Ti-6Al-4V surfaces are potential candidates for use in implant abutments for preventing peri-implant diseases. [ABSTRACT FROM AUTHOR]

Enantio-discrimination and spin-dependent electrochemistry (SDE), as a manifestation of the chirality-induced spin selectivity (CISS) effect, are important phenomena that can be probed by "chiral" electrochemistry. Here, we prepared chiralized surfaces of gold and nickel, to serve as working electrodes, through effective chemisorption of enantiopure dimethyl-bis(ethylenedithio)-tetrathiafulvalene (DM-BEDT-TTF) 1, tetramethyl-bis(ethylenedithio)-tetrathiafulvalene (TM-BEDT-TTF) 2, and their capped silver nanoparticle (AgNPs) aggregate by simple incubation of the metallic substrates. The effective chemisorption was checked by means of ultrahigh vacuum x-ray photoelectron spectroscopy (XPS) and by electro-desorption experiments, i.e., cyclic voltammetry (CV) scans showing a first electro-desorption peak at about −1.0 V. The Au|1 and Au|2 chiral electrodes were successfully used in CV experiments exploiting chiral redox probes. Finally, the hybrid interfaces Ni|enantiopure 1 or 2|AgNPs served as working electrodes in SDE experiments. In particular, the hybrid chiral interfaces Ni|(R)-2|AgNPs and Ni|(S)-2|AgNPs exhibited a significant spin-filtering ability, as a manifestation of the CISS effect, with average spin polarization values of 15%. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles (AgNPs) were fabricated at room temperature using Grewia asiatica leaf extract. Photocatalytic activity (degradation of organic dye) and biological activities (antibacterial, anti-inflammatory, and anti-arthritic) of AgNPs were also unveiled. The optical and physicochemical properties of silver nanoparticles were characterised using UV-Visible spectrophotometer, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Field Emission Scanning electron microscopy (FESEM) analysis, and Dynamic light scattering (DLS) techniques. The green synthesis was justified using UV-visible spectroscopy. XRD confirmed the crystalline structure of AgNPs. The reducing and capping nature of leaf extract was explained by FTIR. The relative capping of AgNPs was studied using FESEM. The hydrodynamic size and polydispersity index of the fabricated silver nanoparticles were analysed using DLS. The photocatalytic activity of AgNPs was observed over crystal violet dye under visible light resulting in efficient removal. AgNPs were also employed to biological activities indicating good antibacterial activity (against gram-positive and gram-negative bacteria), efficient anti-inflammatory activity, and excellent anti-arthritic activity. This work explains the various applications of AgNPs: an efficient photocatalyst as well as a biomedical weapon. [ABSTRACT FROM AUTHOR]

Lead (Pb) is one of the major heavy metal pollutants that can cause serious health problems to humans and the environment. This indicates that its concentration should be known to learn its levels in various environmental systems, and a powerful and economical analytical technique should be there to do so. In this study we report a simple, rapid, cost-effective and environmentally friendly colorimetric sensor based on biosynthesised AgNPs using Parthenium hysterophorus leaf extract. The biosynthesised AgNPs were characterised by UV-vis, FTIR, XRD, SEM and EDS techniques. These nanoparticles were utilised to develop colorimetric sensor for Pb(II) detection. The developed AgNPs-based colorimetric sensor was sensitive and selective towards Pb(II) with the limit of detections of 2.8 and 0.08 µM by visual and UV-vis detection techniques, respectively. The method also exhibited excellent linearity (R2 = 0.9959) within 0.5 to 100 µM concentration range and precision (intra-day and inter-day %RSD values were 2.78% and 3.40%, respectively). The practical application of the developed AgNPs-based sensor was investigated for colorimetric detection of Pb(II) in various real-world samples such as wastewater effluents, leakage, fresh water, tap water and soft drink. The percent recoveries of the tested samples ranged from 99.5–108% indicating the potential applicability of the technique. In general, the nano-sensor is green, exhibited a potential sensitivity and applicability, and hence, recommended for the detection of Pb(II) ions in various water samples. [ABSTRACT FROM AUTHOR]

Aflatoxins are secondary metabolites produced by certain filamentous fungi such as Aspergillus flavus and may pose severe risks to human health. The presence of aflatoxins in commercial food products such as pistachio can bring severe economic drawbacks during harvest, production, and exportation. This study aimed to reduce aflatoxin levels in raw pistachio by active food packaging film enriched with silver nanoparticles and quinoa peptides and extend the shelf-life. The pistachios contaminated with Aspergillus flavus were packaged in a nanocomposite film enriched with silver nanoparticles, quinoa peptide with antifungal properties, and low-density polyethylene at varying percentages. Then, all samples were stored at 25°C for 30 days. The amount of Aflatoxin B1 and total aflatoxin (B1, B2, G1, and G2) were measured with high-performance liquid chromatography. The results showed that the percentage of film composition and time significantly affected aflatoxin values during storage (P < 0.05). The control sample had the highest amount of aflatoxins, while the sample was packaged with a film containing 35% silver nanoparticles, and the quinoa peptide had the lowest amount of aflatoxin at the end of the storage period. Based on the results obtained, the combined use of silver nanoparticles and quinoa peptides in pistachio packaging reduced aflatoxins and increased the shelf life of raw pistachio. [ABSTRACT FROM AUTHOR]

In this work, we describe a simple strategy for the preparation of a low-cost electrode material based on polypyrrole (PPy) film grown on an insulating cellulosic paper substrate via in-situ oxidative polymerisation technique and functionalised by silver nanoparticles (AgNPs) uniformly dispersed on its surface. The properties of the obtained AgNPs-PPy composites were characterised using X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray analysis. The electrocatalytic activity of the prepared electrode was investigated for the electroreduction of nitrate using cyclic voltammetry in 0.1 M KOH solution. Results demonstrated that the incorporation of AgNPs into the PPy matrix improves significantly the catalytic behaviour of this film. The effect on the electrode response of the amount of the incorporated AgNPs was also investigated. This paper highlights a simple procedure for the making of low-cost paper electrodes for the efficient reduction of nitrates. [ABSTRACT FROM AUTHOR]

This study was focused on the design and development of a new heterogeneous catalyst based on polyester (PE) fabric modified with graphene oxide nanosheets decorated with silver metallic nanoparticles (PE-rGO/Ag0), using a simple, easy, and effective approach. PE fabrics were coated by sonication with graphene oxide (GO) nanosheets followed by in situ deposition and reduction of silver nanoparticles over the GO surface, covering the PE fabric and producing PE-rGO/Ag0. The crystalline structure, surface morphology and chemical characteristics of the synthesised materials were identified by X-ray diffraction spectroscopy, scanning and transmission electron microscopy analyses (SEM and TEM) and by Fourier-transform infrared spectroscopy (FTIR), respectively. The catalytic performance of the prepared PE-rGO/Ag0 was assessed during the hydrogenation of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of sodium borohydride (NaBH4). Experimental results indicate that PE-rGO/Ag0 with a surface of 6 cm2 (3x2 cm) showed the highest catalytic activity with an apparent reaction rate constant (Kapp) of 0.65 min−1. In addition, PE-rGO/Ag0 activity resulted to be comparable and significantly higher than previously reported values of silver-based catalysts. Remarkable stability values were achieved during different operating cycles without significant degradation in the catalytic activity, suggesting that PE-rGO/Ag0 can be used as a strong candidate in long-lasting chemical catalytic processes. [ABSTRACT FROM AUTHOR]

[Display omitted] Bacterial infection of biomedical implants is an important clinical challenge, driving the development of novel antimicrobial materials. The antibacterial effect of vertically aligned graphene as a nanoarray coating has been reported. In this study, vertically aligned graphene nanosheets decorated with silver nanoparticles were fabricated to enhance antibacterial effectiveness. Vertical graphene (VG) nanoflakes were synthesized by plasma-enhanced chemical vapor deposition (PECVD). Ag nanoparticles were attached to the surface of VG through using polydopamine and achieving a sustained release of Ag+. VG loaded with Ag nanoparticles (VGP/Ag) not only prevented bacterial adhesion for a long time, but also exhibited good biocompatibility. This work provides a new venue for designing antibacterial surfaces based on combination of graphene nanoarrays with other nanomaterials, and the results indicate that this approach could be very successful in preventing implant associated infections. [ABSTRACT FROM AUTHOR]

Preparing bismuth compounds-based heterojunctions with superior redox capability has emerged as a promising strategy for environmental remediation. Herein, p-BiOI/n-Bi 2 WO 6 heterojunctions were successfully obtained via a novel, facile, and green solvothermal method. The heterojunctions were synthesized using different mass ratios (1:2, 1:1, and 2:1) of BiOI (BI) and Bi 2 WO 6 (BW), with 1:1 as the best ratio, which was decorated with silver nanoparticles (Ag-NPs) and nitrogen-doped graphene (NG) applying green methodologies. The as-prepared BI/BW heterojunctions were characterized by several techniques, and their adsorption capacity and photodegradation activity toward tetracycline (TC) under 19 W visible LEDs illumination were investigated. The capacity of pure BI, BW and BI/BW heterojunctions for adsorbing TC ranged from 14 to 68 mg/g; among the heterojunctions, Ag/1BI/1BW showed the highest TC adsorption capacity, 35 mg/g. Moreover, the photocatalytic tests revealed that the Ag/1BI/1BW exhibited the highest catalytic performance, achieving a TC percentage degradation of 81 % within 120 min. The low nominal power consumption of the LED-based photoreactor (0.0475 kWh) was significantly lower than that reported in the literature for using Xe or Hg lamps. In addition, catalyst dosage, initial TC concentration, and solution pH were investigated, demonstrating that they play important role in TC photodegradation. Scavenger assays determined that the degradation of TC using Ag/1BI/1BW proceeds mainly via superoxide radicals and holes, which agrees with the carrier transfer mechanism postulated for this heterojunction. TOC analysis revealed that the efficiency of Ag/1BI/1BW was 63 %, and reuse tests confirmed its high performance even after three cycles. This research provides new insights into the design of high-performance heterojunctions for water treatment. [ABSTRACT FROM AUTHOR]

Biobased coating material is required to replace synthetic polymer-based paper coating material for a safe and clean environment. The study aimed to investigate the use of biobased nanocomposites as a coating material for paper. The biobased nanocomposite was prepared using nanocellulose, sodium alginate (SA), and bio-synthesized silver nanoparticles (AgNPs). Nanocrystalline cellulose (NCC) was produced through acid hydrolysis, followed by fractionation. The average size of the crystals was 15 nm in width and 125 nm in length. AgNPs were prepared by the reduction of AgNO3 with lignin. The synthesis of silver nanoparticles was confirmed by UV–visible and FTIR spectroscopy. SA-NCC composite coating improved the barrier and strength properties of paper. The paper with composite coating demonstrated a 29.11 % increase in tensile index in the cross direction, 20.82 % increase in the machine direction, and 77.89 % improvement in burst index at a coating weight of 1.68 g/m2. The composite-coated paper showed better air barrier and lower water absorption characteristics than sodium alginate-coated paper. The incorporation of AgNPs in the coating mixture introduced the antimicrobial activity of the paper as well. [ABSTRACT FROM AUTHOR]

The review summarizes the results of experimental studies of physiological processes occurring in the organism of higher plants during their interaction with silver nanoparticles. According to the available data, silver nanoparticles can be internalized by plant roots and leaves and then transported throughout the plant organism via the apoplastic and symplastic pathways. When silver nanoparticles enter the plant's body, they trigger a cascade of intracellular reactions. Depending on exposure conditions, silver nanoparticles can both have a positive effect, such as increased plant growth and activation of specific and nonspecific plant defense mechanisms, and a negative effect, such as plant development inhibition. The key factors determining the effect of silver nanoparticles on higher plants, such as the dosage and the route of exposure, as well as the physicochemical parameters, including the size of nanoparticles and the nature of the surface stabilizer were reviewed. Promising directions for further research were considered. [ABSTRACT FROM AUTHOR]

A novel ultra-wideband (UWB) flexible metamaterial absorber (MA) is proposed and thoroughly examined both numerically and experimentally for microwave range applications. The design is based on a rectangular ring array of silver nanoparticles (SNP) inkjet-printed on an ultra-thin flexible Polyethylene terephthalate (PET) substrate. The finite integration technique (FIT) is employed to simulate the proposed design. The results demonstrate absorption performance surpassing 90% across a wide frequency span, ranging from 3 to 96.4 GHz, for both transverse electric (TE) and transverse magnetic (TM) polarizations under normal incidence. The surface current and electric field distributions at different frequencies reveal the underlying physical mechanisms responsible for the UWB absorption phenomenon. Perfect absorption is due to the intrinsic character of the metamaterial structure that can be confirmed from the extracted effective permittivity and effective permeability. The proposed design is fabricated and experimentally tested, demonstrating good agreement with the simulation outcomes. The metamaterial absorber's remarkable characteristics make it highly promising for various applications in communications and stealth, primarily due to its perfect absorptivity over the UWB frequency range. [ABSTRACT FROM AUTHOR]

Developing an eco-friendly method for producing nanomaterials is an area of significant research and commercial interest owing to its numerous applications in various disciplines. This study used a simple green synthesis approach to produce silver nanoparticles (AgNPs) using Porella pinnata L. aqueous extract. Phytochemical constituents of P. pinnata were identified by Gas Chromatography and Mass Spectroscopy (GC-MS). The optical, structural, and morphological characteristics of the AgNPs were found using UV visible absorption spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), Zeta Potential, and scanning electron microscope (SEM). The AgNPs had an average size of 76–84 nm and were mostly spherical. Considering the antimicrobial and antibiofilm activity results, both aqueous extract and AgNP have significant activities against different microorganisms based on the disc diffusion, broth microdilution, and antibiofilm methods. The P. pinnata and AgNPs extracts were significantly inhibited all test culture especially Acinetobacter baumanii ATCC 19606. The agarose gel electrophoresis method showed that extract and AgNP both cleaved DNA by hydrolytic and oxidative. Although both P. pinnata and AgNP extracts have dose-dependent antioxidant activity, AgNP is more effective. Thus, green synthesis AgNPs may be a new alternative therapeutic agent for infection therapy. [ABSTRACT FROM AUTHOR]

A multifunctional nanostructured hybrid composed of metal–protein–ceramic was designed and then synthesized using three different methods: chemical reduction, physical adsorption, and coprecipitation. The processes yielded colloidal spherical silver nanoparticles (AgNPs) enveloped in a bovine serum albumin (BSA) corona, leading to the core–shell structure AgNPs–BSA. To enhance biocompatibility and mitigate potential toxicity associated with metallic nanoparticles, this core–shell structure was coated with a layer of calcium carbonate (CaCO3). In order to analyze the internal structure of the resulting hybrid nanostructure (AgNPs–BSA–CaCO3), a number of samples were produced by focused ion beam (FIB) and characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and zeta potential (ζ) measurements. The cytotoxic effect of the samples were evaluated through in vitro tests on mouse macrophage cell line RAW 264.7 ATCC TIB‐71, this was accomplished by calculating the appropriate concentrations from the dose–response curve of AgNPs. Research showed that the AgNPs–BSA–CaCO3 mixture triggered the formation of vaterite; these findings were corroborated by FTIR and Raman techniques. The spherical nanostructures have an average diameter size of 4.3 ± 2 μm and an average roughness (Ra) of 3.11 ± 0.62 μm. Zeta potential (ζ) and isoelectric point studies reveal that this hybrid nanostructure exhibits amphoteric behavior that differs from either AgNPs or AgNPs–BSA alone. Cell viability response exceeded 75%, indicating the noncytotoxic nature of the proposed hybrid nanostructures. [ABSTRACT FROM AUTHOR]

In recent years, nanotechnology has revolutionized various sectors, particularly in nanomedicine, where nanomaterials are used for diagnosis, monitoring, control, prevention, and treatment. Among these, silver nanoparticles (AgNPs) stand out due to their remarkable antimicrobial and cytotoxic properties. Traditional chemical synthesis of AgNPs poses significant environmental and health risks. This study introduces a novel, eco‐friendly synthesis method using royal jelly (RJ), a nutrient‐rich secretion from honeybees, to produce AgNPs with potent anticancer effects. Our research provides a detailed investigation into RJ‐mediated AgNPs' modulation of the VEGFa/PI3K/Akt/MMP‐2 pathway in HeLa and A549 cancer cell lines. AgNP characterization was performed by applying UV–Vis spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM) in combination with selected area electron diffraction (SAED). Cell signaling system components were determined by ELISA analysis. The cells were subjected to staining with hematoxylin and eosin to visualize the treatment's effects. This study focuses on the green synthesis of AgNPs using RJ and its bioactivity against cancer cells. It provides a detailed characterization of the nanoparticles and examines their effects on cancer cells, specifically HeLa cervical cancer and A549 lung cancer cell lines. Green synthesized AgNPs demonstrate significant cytotoxic effects against HeLa and A549 cancer cell lines. The underlying molecular mechanisms contributing to their anticancer activity were elucidated. Our findings revealed a significant decrease in arginase activity upon exposure to AgNPs, accompanied by reductions in PI3K and phosphorylated and total Akt levels, indicative of pathway inhibition. Additionally, RJAgNP demonstrated a capacity to reduce nitric oxide levels and suppress angiogenesis‐related factors like VEGF and MMP‐2 and inflammation‐related factors like TNF‐α and COX‐2, thus impeding angiogenesis and metastasis. Moreover, our results shed light on the involvement of reactive oxygen intermediates (ROIs) in mediating apoptotic pathways, as evidenced by the increase in malondialdehyde (MDA) concentration and the corresponding decrease in Akt levels, ultimately promoting death in cancer cells. Our study contributes significantly to the field of nanomedicine and cancer therapy by introducing the use of green synthesis AgNPs using RJ and providing in‐depth insights into their molecular mechanisms of anticancer action. Our research findings demonstrate the anticancer potential of RJ‐AgNPs by targeting the VEGFa/PI3K/Akt/MMP‐2 pathway and modulation of ROS/RNS in cancer cells. [ABSTRACT FROM AUTHOR]

In this study, it is aimed to increase the wear and fatigue performance of aluminium‐based sliding bearing material by using silver nanoparticles (AgNPs) added lubricant and shot‐peening process. The main purpose is to minimise the wear of the bearing material by penetrating AgNPs added lubricants into the rough surfaces formed by shot peening. Almen intensity, coverage and shot size parameters in the shot‐peening process were analysed in terms of hardness, surface roughness and fatigue strength. The shot‐peened aluminium bronze was subjected to wear experiments under dry, pure water and AgNPs added lubricant conditions. The wear test results were analysed in terms of friction coefficient, wear volume and surface roughness parameters, and the interaction of lubricant and shot‐peening parameters was evaluated. According to the results of the shot‐peening experiments, the Almen intensity was the most effective parameter in terms of hardness and surface roughness (91.62%). It was concluded that the hardness value was 8% higher at high Almen (12–14A) intensity compared with low Almen intensities, and the shot‐peening process could increase the fatigue strength by ~21 times. According to the wear tests, the most effective parameters were 4–6 Almen intensity and AgNP‐added lubricant. [ABSTRACT FROM AUTHOR]

Microfluidics made of dimethylpolysiloxane were developed for chemical synthesis using microwave heating at 24.125 GHz, and microwave efficiency was enhanced by the microwave resonance effect. In addition, the device was fabricated using a mold created using a 3D printer to reduce production costs. The microchip structure comprised a post‐wall waveguide and a microchannel that passed through the waveguide. This post‐wall waveguide also comprises metal columns (post‐wall) instead of a conductor side wall, and easily introduces microchannels through the gaps between the metal columns. The waveguide length was adjusted to achieve a resonance frequency of 24 GHz using an electromagnetic wave simulation, assuming that the microchannel was filled with pure water. Microwaves with an input power of 4 W caused a maximum temperature increase of 93 °C; this result is ~10 °C higher than that of a microchip with non‐resonant structure. In this study, Ag nanoparticles were synthesized using a chemical reaction induced by microwave irradiation of a chip flow system. Owing to irradiating the mixing reagent with microwaves of an input power of 4 W while controlling the flow rate at 0.7 μl/min, the formation of Ag nanoparticles with an average particle size of ~19.2 ± 2.4 nm was demonstrated by absorbance measurements and dynamic light scattering. It is expected that microwave microfluidics enhanced by the resonance effect will substantialize nanoparticle synthesis and high‐efficiency automated chemical synthesis combined with multichemical unit operations. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Recently, metal and metal oxide nanoparticles have garnered significant scientific interest due to their distinctive properties and promising applications across diverse fields. This study details the successful synthesis and characterization of Fe3O4, Ag, and magnetite/silver core-shell (Fe3O4/Ag) nanocomposites, prepared through chemical reduction and co-precipitation methods. The successful incorporation of Ag into Fe3O4 nanoparticles was confirmed through X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. Physical characterization revealed that the synthesized nanoparticles were small in size and highly pure. Their optical and electrical properties, including bandgap and electrical conductivity, were also characterized. The antibacterial activity of the synthesized Fe3O4, Ag, and Fe3O4/Ag nanoparticles was evaluated using Minimum Bactericidal Concentration (MBC) against pathogenic bacterial strains: S. typhimurium, P. aeruginosa, and S. aureus. The results demonstrated that Ag, Fe3O4, and Fe3O4/Ag nanoparticles could inhibit high concentrations of bacteria, indicating an excellent antimicrobial effect. Furthermore, the Fe3O4/Ag nanoparticles were found to be more effective than both Fe3O4 and Ag nanoparticles in inhibiting the selected pathogenic bacteria strains: S. typhimurium, P. aeruginosa, and S. aureus. [ABSTRACT FROM AUTHOR]

In this study, an operative technique was presented for the synthesis of the magnetically separable γ-Fe2O3@SiO2@ZIF8@Ag photocatalyst. The synthesized nanostructures were identified using various structural analyses, including XRD, EDX/SEM, FTIR, bandgap, and VSM. Their ability to remove norfloxacin (NOR) was then examined by studying the effects of various parameters, including photocatalyst dose, solution pH, initial NOR concentration, and reaction time. The results showed that the catalyst had the best performance, with an efficiency of 100% under UV light and 96.2%unnder visible light, at a catalyst dose of 0.4 g/L and a reaction time of 45 min. Stability tests also showed that the synthesized photocatalyst maintained its proper performance after five cycles, and its efficiency was reduced by only 4.5%. Also, a comparison between the adsorption and the photocatalytic process showed that the adsorption process removed only 42% of NOR after 60 min, whereas the photocatalytic process, under both visible and UV light irradiation, was able to eliminate 100% of NOR in the same time period. The results showed that the degradation kinetics follow the first-order kinetic model. The reaction rate constants using UV and visible lamps were 0.082 and 0.056 min− 1, respectively, which indicates the degradation rate for UV light is 1.46 times higher compared to visible light. Also, the half-life times for the process with UV and visible light were 8.4 and 12.3 min, respectively. The average oxidation state (AOS) and carbon oxidation state (COS) of the process increased over time, indicating good degradation of NOR and conversion of non-biodegradable wastewater into biodegradable wastewater. Reactive oxygen species (ROS) assays showed that hydroxyl radicals and holes have the main role in the degradation process. Therefore, the proposed photocatalysts can be considered suitable, cost-effective, and reusable for the treatment of hospital wastewater. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic highlighted the urgent need for improved personal protective equipment (PPE). Green-synthesised silver nanoparticles (AgNPs) using pandan (Pandanus amaryllifolius) extract offer a sustainable solution to enhance PPE effectiveness against infectious diseases. This eco-friendly approach utilises pandan's bioactive compounds to reduce silver ions into nanoparticles, providing a sustainable alternative to conventional chemical synthesis methods. The resulting AgNPs exhibit potent antimicrobial and antiviral properties, making them valuable for incorporation into PPE fabrics and coatings. Beyond antimicrobial benefits, pandan-derived AgNPs may impart natural fragrances and skin-soothing properties, enhancing user comfort. The green synthesis process reduces environmental impact and potential toxicity associated with conventional chemical methods. While challenges in scaling production, ensuring regulatory compliance, and assessing long-term health and environmental effects persist, pandan-derived AgNPs-coated PPE represents an innovative approach to infection prevention. This technology has the potential to significantly improve safety measures in healthcare and other high-risk environments while promoting sustainability. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are increasingly recognized as vital nanomaterials in biomedical applications due to their diverse pharmacological properties, including antimicrobial and anti-neoplastic effects, particularly when derived from herbal sources. This study aims to synthesize AgNPs employing a sustainable approach aligned with the principles of the sustainable development goals. The synthesized AgNPs are incorporated with doxorubicin (DOX) and encapsulated within polylactide nanoparticles to enhance their anticancer potency. AgNPs are prepared via the reduction of silver ions using rutin as a reducing agent, with the reaction progress monitored via ultraviolet-visible spectroscopy (UV-vis). Subsequently, the AgNPs are encapsulated into poly(D, L-lactic acid) (PDLLA) nanoparticles alongside doxorubicin. The developed nanoparticles have shown a diameter size of 233 nm with a zeta potential of -21.47 mV. Moreover, the in vitro release profile of the DOX showed a sustained release kinetics over 30 h. Evaluation of the AgNP-DOX-loaded PDLLA nanoparticles reveals enhanced anticancer activity against HeLa and HepG2 cancer cells, highlighting the synergistic efficacy of the combined therapy. These findings underscore the potential of AgNPs-based formulations as promising candidates for advanced cancer therapeutics. [ABSTRACT FROM AUTHOR]

This study developed a novel paper-based sensor for the simultaneous analysis of ascorbic acid (AA) and hydroquinone (HQ). The sensor utilized polyvinyl alcohol (PVA)-stabilized silver nanoparticles (AgNPs-PVA) as the reagent probe and PVA media acted as the filter for separation of the analytes. Polydimethylsiloxane (PDMS) and ethanol serve as the stationary phase and eluent, respectively, exploiting the differences in analyte reactions and solubility to achieve their separation on the filter paper. The circular sensor's central zone was AA's detection area, while HQ was detected in the outer ring region. AA induced an immediate color change in the test kit, whereas HQ required a 20-minute elution with ethanol followed by colorimetric analysis. All analytes exhibited relative standard deviations of repeatability and reproducibility below 2.7% and 9.5%, respectively. Under optimal conditions, the linear detection range for HQ was 0.2-2.0 mg⋅L− 1, while AA was 0.1-2.0 mg⋅L− 1. The detection limit was determined to be 0.05 mg⋅L− 1 for AA and 0.1 mg⋅L− 1 for HQ. The recoveries of AA and HQ in cosmetic cream samples ranged from 80 to 110%. The accuracy of the sensor's measurements was further validated by comparison with the HPLC-DAD method. [ABSTRACT FROM AUTHOR]

Obtaining new materials with antibacterial activity is an urgent task due to the emergence and proliferation of new antibiotic resistant strains, as well as the increasing requirements for the effectiveness and toxicity of such materials. Electrical explosion of two twisted wires (EETW) to produce of heterophase nanoparticles is attractive for develop novel antibacterial agents. Our work describes simple and environmental friendly way to obtain novel composite CuO/Cu2O/Ag nanoparticles with different silver mass ratio (15, 50, 90%) by the simultaneous electrical explosion of Ag and Cu twisted wires in oxygen containing atmosphere. The using of EETW for the production of heterophase NPs is due to several advantages such as high purity of nanoparticles, good productivity (about 120 g nanoparticles per hour) and eco-friendliness. The obtained nanoparticles have irregular spherical shape morphology. According to EDX analysis dates, the nanoparticles have Janus-like structure, where one part is enriched with Ag and the other with Cu and O. The mean particle size depended on silver content and was 63 ± 2 nm (90% Ag), 92 ± 2 nm (15% Ag). CuO/Cu2O/(50)Ag particle size distribution have two peaks, one at 35 ± 1 nm and the other at 79 ± 2 nm. The NP zeta potential of nanoparticles measured neutral pH and 25 °C was positive (more than 20 mV). CuO/Cu2O/Ag nanoparticles with 50% Ag significantly inhibited the growth of methicillin-resistant Staphylococcus aureus (MRSA) with MIC = 62 µg/mL. The antibacterial activity nanoparticles with 90%Ag determined by the disco-diffusion method was slightly lower than that of the nanoparticles with 15 and 50% Ag. The possible antibacterial mechanisms may be attributed to the synergistic effect of the heterostructure of EETW nanoparticles and the formation of galvanic nanopairs. The presence of silver metal and copper oxides in nanoparticles can promote galvanic corrosion, leading to the release of more metal ions into the bacterial suspension. We have shown that the nanoparticles obtained have a positive zeta potential, unlike Ag nanoparticles, which may contribute to a better adhesion of nanoparticles to the surface of bacterial cells. The synthesized NPs have broad potential to be developed in pharmaceutics as an effective antimicrobial nanomaterial. [ABSTRACT FROM AUTHOR]

This study focuses on the immobilization of horseradish peroxidase (HRP) on modified acrylic fabrics incorporating gold and silver nanoparticles. The process involves treating the acrylic fabrics with hydroxylamine hydrochloride and then coating them with silver and gold nanoparticles. Both obtained materials, treated acrylic fabrics-coated with silver nanoparticles (AgNPs@TA-HAC) and treated acrylic fabrics-coated with gold nanoparticles (AuNPs@TA-HAC), were utilized as supporters for HRP. The physicochemical properties of modified acrylic fabrics were investigated using FTIR, SEM, and zeta potential. HRP immobilized on AgNPs@TA-HAC displayed an activity of 69 units/g support with a specific activity of 4.55 units/mg protein, whereas HRP immobilized on AuNPs@TA-HAC demonstrated an activity of 76 units/g support with a specific activity of 4.75 units/mg protein. After the 15 repetitive cycles, the immobilized HRP on AuNPs@TA-HAC and AgNPs@TA-HAC retained 75 and 59% of their enzymatic activity, respectively. The immobilized HRP on both material supporters retained its activity better compared to the free HRP when exposed to all tested organic solvents. The Michaelis constant (Km) for free HRP and HRP immobilized on AuNPs@TA-HAC and AgNPs@TA-HAC were determined to be 6.23, 8.65, and 9.11 mM, respectively. The maximum reaction rates (Vmax) for the immobilized HRP on both supports were slightly reduced at 0.71 and 0.69 U/mL, compared to 0.74 U/mL for free HRP. This approach of utilizing acrylic fabrics and metal nanoparticles provides a promising method for enzyme immobilization, with potential applications in various industries. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) were synthesised utilising a one-pot green synthesis process using phytonutrients obtained from Houttugniae herba (HH) as a reductant and stabiliser. The proposed technique was fast, simple, eco-friendly, and cost-effective, and it does not require any additional processing or toxic ingredients to reduce and stabilise the AgNPs. All parameters (concentration of HH, reaction duration, temperature, and pH) involved in the reduction/stabilisation reaction were evaluated using a one-factor-at-a-time (OFAT) technique in a set of the experimental array to establish an optimal reaction state. Intense yellow colour and a prominent peak at 411 nm in the UV–vis absorption spectra indicated the growth of AgNPs in the reaction system. The produced AgNPs deploying optimum parameters were nearly spherical, with nanometre size (16.28 ± 4.48 nm), highly crystalline (d-spacing = 0.234 and 0.258 nm), and well stabilised (zeta potential = −26.4 mV). The measurement and analysis also yielded that the AgNPs were formed by an oxidation-reduction reaction between plant-derived phytonutrients and metal precursors and subsequently stabilised by the encapsulation of phytonutrients. The biogenic AgNPs exhibited remarkable antibacterial effectiveness against gram-positive and gram-negative bacteria. In addition, the AgNPs demonstrated significant catalytic degradation and mineralisation of industrially essential di-azo dyes with a degradation efficiency of nearly 100% within 20 min. The present investigation shows a simple and environmentally friendly way to synthesise AgNPs, which might be feasible to meet the current need for bacterial reduction and textile wastewater treatment. [ABSTRACT FROM AUTHOR]

This research work explores the green synthesis of silver nanoparticles using Quassia indica (QI-Ag NPs), a natural plant extract, as a stabilizing and reducing agent. The synthesized QI-Ag NPs were characterized using various analytical techniques, including UV-Visible spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Transmission Electron Microscopy (HR-TEM) and Selected Area Electron Diffraction (SAED). The UV-Visible analysis revealed a characteristic peak at 430 nm, indicating the successful formation of AgNPs. XRD analysis unveiled the crystalline nature of the nanoparticles, with four distinctive peaks corresponding to the silver crystallographic planes. SEM and EDX provided insights into the morphology and chemical composition of the QI-AgNPs. Moreover, TEM and SAED elucidated the structural attributes and crystallinity of the nanoparticles. The Ag NPs exhibited a spherical structure and crystalline nature, as supported by both SAED and XRD findings. The zeta potential of QI-Ag NPs exhibited a value of −24.2 mV. The synthesized QI-Ag NPs were evaluated for their photocatalytic potential, demonstrating a remarkable 97% degradation of Crystal Violet dye. Furthermore, comprehensive studies encompassing antioxidant, antimicrobial and cytotoxicity assessments were conducted, showcasing the multifaceted applications of these nanoparticles. This research underscores the promising potential of Q. indica-mediated silver nanoparticles as environmentally benign and versatile nanomaterials. [ABSTRACT FROM AUTHOR]

The biogenic synthesis of silver nanoparticles (AgNPs) are gaining attention because they are eco-friendly, non-hazardous, economical and devoid of the drawbacks of physicochemical processes. Biogenic approaches for synthesizing nanoparticles (NPs) using plant leaves, seeds, bark, stems, fruits, roots and flowers are highly cost-effective compared to other methods. Silver (Ag) has been used since ancient times, but biogenic AgNPs have only been made in the last few decades. They have been employed primarily in the food and pharmaceutical industries as antimicrobials and antioxidants. Recent studies have confirmed that many molecules present in different bacteria, including Escherichia coli, Staphylococcus aureus, Citrobacter koseri, Bacillus cereus, Salmonella typhi, Klebsipneumoniaoniae, Vibrio parahaemolyticus, Pseudomonas Aeruginosa, are bound to the AgNPs and can be inhibited using multifaceted mechanisms like AgNPs inter inside the cells, free radicals, ROS generation and modulate transduction pathways. Recent breakthroughs in nanobiotechnology-based therapeutics have opened up new possibilities for fighting microorganisms. Thus, in particular, biogenic AgNPs as powerful antibacterial agents have gained much interest. Surface charge, colloidal state, shape, concentration and size are the most critical physicochemical characteristics that determine the antibacterial potential of AgNPs. Based on this review, it can be stated that AgNPs could be made better in terms of their potency, durability, accuracy, biosecurity and compatibility. [ABSTRACT FROM AUTHOR]

In this research work, the silver nanoparticles (NPs) were produced by hydrothermal method. The silver nanoparticles powder thus obtained was characterised by Ultraviolet – visible spectroscopy, X-Ray Diffraction Analysis (XRD), Scanning Electron Microscopy (SEM). The UV-V spectrophotometry for various samples showed that NPs formed in range of 390 nm to 470 nm. The XRD analysis resulted in the calculation of correct size of silver nanoparticles by Scherer's equation and the size was 33.63 nm. The prepared silver nanoparticles were coated to copper electrode by SILAR technique and used in machining die steel (EN31) material by Electric Discharge Machine (EDM). The influence of process variables such as discharge current, duration of pulse on and pulse-off on the metal/material removal rate, was studied using random surface methodology (RSM). It has been observed that MRR was highest for the electrode produced by powder metallurgy with 9% silver nanoparticles and was 0.225065388 gms/min. Similarly, TWR was found lowest as 0.0005 gm/min at the electrode prepared with SILAR coated technique for particular concentrations of A (0.001 M AgNO3, 0.002 M NaBH4) and B (0.002 M AgNO3, 0.004 M NaBH4) for dipping cycles of 25, 50 and 75. It has been clearly evident that the tool electrodes prepared by powder metallurgy by mixing silver nanoparticles by weight percentage yielded great results, particularly tool electrodes prepared by mixing 9% of silver nanoparticles in copper powder matrix yielded in significant increase with 6.85% in MRR and reduction TWR by almost 10%. The reason for the improvement in MRR is due to the noticeably substantial action of the spark for a longer duration, which made more high energy electrons impinging on the work material. [ABSTRACT FROM AUTHOR]

Design and development of novel eco-friendly materials with outstanding antimicrobial properties have transpired to impede and regulate the growth of pathogenic microorganisms. Bionanocomposites are the propitious aspirant to circumvent the global warming emanates and proliferation in pollution attributed to biocompatibility, degradability, and environmental benign primacy. Undoubtedly, silver nanoparticles are the magic bullet that has efficient antimicrobial properties against various bacterial strains. The synchronous existence of chitosan and Ag nanoparticles are the two crucial protruding antibacterial agents that divulged imperious antibacterial properties against gram-positive strains in comparison to gram-negative strains. This indagation will shed light on the experimentation and analysis of chitosan/PVA biohybrid grafted with graphene and silver nanoparticles for screening of antibacterial efficiency. The tensile strength of 15% GO/CS/Ag/PVA was found to be 81.99 MPa as compared to pristine chitosan which was 36 MPa. The active resultant bio-nano hybrid fabricated via a biomimetic approach evinced magnificently thermostable, mechanically robust, and antibacterial properties which make it a potential candidate for packaging applications. The results revealed that the inhibition is relatively dependent upon concentration. It has been noticed that a better antibacterial effect was shown by gram-positive bacteria contrary to gram-negative strains for GO-reinforced CS films owing to the presence of silver nanoparticles. [ABSTRACT FROM AUTHOR]

In the current investigation, pomegranate peel extract was employed to create silver nanoparticles. The produced nanoparticles were characterized using a variety of spectroscopic studies (PGP-AgNPs). Using the well diffusion method, the antibacterial effectiveness of PGP-AgNPs was investigated. Moreover, PGP-AgNPs' effect on free radicals was assessed. The absorbance of the nanoparticles is maximum at 449 nm in the ultraviolet-visible spectrum. Phenols in the peel extract were implicated in capping the PGP-AgNPs, according to the Fourier transform infrared spectra. X-ray diffraction and transmission electron microscopy investigation confirmed the crystalline form and spherical morphology of the nanoparticles with an average size of 37.92 nm. With regard to Escherichia coli and Staphylococcus aureus, the PGP-AgNPs have the strongest and weakest growth inhibitory activity. Against DPPH, hydrogen peroxide, and nitric oxide radicals, the PGP-AgNPs demonstrated strong radical scavenging capabilities. Hence, manufactured nanoparticles were a promising option for developing an antibacterial and antioxidant drug. [ABSTRACT FROM AUTHOR]

Global health and ecosystem concerns over mercury pollution require stringent monitoring. Herein, we showcase a novel approach for detecting trace Hg2+ ions in water using cyclic voltammetry (CV). Our approach involves modifying glassy carbon electrode (GCE) and screen printed electrode (SPE) surfaces with a nanocomposite of ascorbic acid-capped silver nanoparticles (AsAgNPs) embedded in nanocrystalline bacterial cellulose (AsAgNP-NBC). Analytical techniques confirmed the nanocomposite's stability and morphological characteristics, exhibiting high accuracy within a linear range of 10 nM to 1 µM Hg2+ and a low limit of detection (LOD) of 3.531 nM. Additionally, on irradiation with 455 nm light source, AsAgNP-NBC modified SPE displayed a remarkable 9.6 times enhanced photocurrent, achieving an LOD of 3.95 pM, and enhanced photoresponsivity of 55.2 mA W−1, showcasing its potential for ultra-trace level detection. This cost-effective and biocompatible nanocomposite presents a promising alternative to conventional analytical methods for selective detection of trace Hg2+ ions in environmental samples. [ABSTRACT FROM AUTHOR]

Tomato (Solanum lycopersicum L.) holds significant importance as a primary vegetable crop globally. In this research, the extracellular green-synthesis of silver nanoparticles was accomplished by using some Gram positive bacteria. Three isolates including KM59, SM88, and KM93 exhibited the highest nanoparticle biosynthesis activity. The isolates were identified according to colony morphology and the 16S rRNA gene sequence identities, as Streptomyces spp. The obtained AgNPs were characterized by TEM and exhibited various shapes, including hexagonal, pentagonal, spherical, and triangular. The MIC for Ralstonia solanacearum was determined to be 25, 6.25, and 25 µg/mL for the AgNPs93, AgNPs88, and AgNPs59, respectively. The MIC of AgNPs93, AgNPs88, and AgNPs59 against Xanthomonas campestris was assessed at concentrations of 25, 12.5, and 50 µg/mL, respectively. In the case of Alternaia alternata, the MIC for AgNPs93 and AgNPs59 was found to be 50 µg/mL, while for AgNPs88, it was 25 µg/mL. Furthermore, the MIC of AgNPs88 against Rhizoctonia solani was determined to be 12.5 µg/mL, whereas for AgNPs93, it was 25 µg/mL, and for AgNPs59, it was 50 µg/mL. Disease index was reduced (AgNPs88 demonstrated the most potent inhibitory effect, whereas AgNPs59 displayed the least inhibitory effect) when tomato plants inoculated with fungal and bacterial pathogens treated with the AgNPs at MIC concentrations. The cytotoxicity of AgNPs on the B16F10 cancer cell lines determined by the means of MTT assay. Biosynthesis of AgNPs using Actinobacteria is an eco-friendly process. In agriculture, medical sciences, and industry, process optimization can become a valuable technology for mass production. [ABSTRACT FROM AUTHOR]

Healthcare-associated infections (HAIs) cause economic and social burden by affecting millions of patients annually, especially in low-income countries. The treatment of HAIs with antibiotics can lead to their increased resistance and subsequently increased mortality. As an alternative solution, nanomaterials combined with inorganic metals (silver ions and silver-based compounds) have been proposed. In this study, after extraction of sodium silicate from rice husk ash, silver-coated silica nanoparticles (SiO2@Ag-NPs) were synthesized by sol-gel method and evaluated the antibacterial activity against hospital-acquired infections. SiO2@Ag-NPs were analyzed by transmission electron microscopy (TEM). The antibacterial activity of SiO2@Ag-NPs against two clinical isolated bacterial strains, including methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii, was assessed using minimum inhibitory concentrations (MICs) and using scanning electron microscopy (SEM). TEM images showed that SiO2 nanoparticles had a uniform shape with a size of around 50 nm SiO2@Ag-NPs' surface area and homogeneous pores are 78 m2/g and 2.71 nm, respectively, with purity over 98%. Silver nanoparticles attached to SiO2 surface have uniform shapes with size smaller than 5 nm. The MIC results were determined from 25 to 400 ppm depending on the concentration and bacterial strain tested. SEM images showed that SiO2@Ag-NPs inhibited established biofilms in both bacterial strains, discrete bacterial cells, and fewer clusters. There was no or little extracellular matrix observed, the cells were distorted, shrank, ruptured, and appeared to have indentation or perforation in the cell wall. The results showed that SiO2@Ag-NPs were an attractive nanomaterial for commercial applications and in treating diseases associated with microbial infections. [ABSTRACT FROM AUTHOR]

Metallic nanoparticles (Au and Ag) were synthesized through simple, rapid, eco-friendly and an economical method with a new cell-free filtrate Fusarium pseudonygamai TB-13 cell as both reducing and stabilizing. The desired nanoparticles (Ag and Au) were optimized using response surface methodology (RSM) to reach the maximum yield of NPs. To attain the ideal reaction state, the central composite face design and the efficient variables in the environmentally friendly synthesis reaction were utilized. Temperature, pH, and precursor concentrations were determined to be the most useful variables for producing Au and Ag nanomaterials. An acceptable foot was employed in the model's realization. The various elements were optimized using surface plots, contour plots, pareto charts,, analysis of variance (ANOVA), normal probability-plots, interaction plots, including effect-plots, and surface plots. A significance criterion of 5% was applied to each and every element. Some of the possible relationships between these variables also had an impact on the production process. The suggested predictive model provided a very good match to the data obtained from experiments. In comparison to conventional optimization methodologies, the study's findings examined whether or not more biofabrication was achievable under ideal fermentation-conditions for the production of Au and Ag nanoparticles. [ABSTRACT FROM AUTHOR]

Polymers blending has attracted significant interest in recent years owing to the possibility of synergistic interactions between blended materials which can be impressively beneficial over single substrates. Herein, a Tara gum derivative-(PVA-TG) blend was exploited as stabilizing agent for the synthesis of cyto-compatible PAPBA/(PVA-TG)/Ag, colloidal nanocomposite. Based on the in-situ oxidative polymerization strategy, 3-aminobenzene boronic acid (ABBA), was used for the reduction of silver salt, inside highly hydrophilic (PVA-TG) blend. As a result, AgNPs is formed, while ABBA, is oxidized to its conducting polymer conformation (PAPBA), all within the blended polymers solution. PAPBA/(PVA-TG)/Ag, showed dose-dependent cell viability with IC50 of 3.9 µg/mL against human keratinocytes (HaCaT) cells, based on in vitro MTT assay, which attested to its cyto-compatibility. The material was fully characterized using various analytical equipment and was deployed for the detection of metal ion (Au3+ ion) in solution. At the optimal detection conditions, absorbance ratios, (A560/A429) displayed linearity with Au3+ concentrations from 0.10 to 10.0 & 10.0–80.0 µM, with 28.5 nM detection limit (LOD). Further, the mechanistic basis of the detection strategy was proven to be based on galvanic replacement and was applied to Au3+ detection/monitoring in environmental samples with reliable precision and accuracy (99.4–102.3%). In all, we have showcased an innovatively contrived synthesis strategy which can be of huge benefit in toxic metal ions monitoring in water samples. [ABSTRACT FROM AUTHOR]

Infection is a major concern in surgery involving grafting and should be considered thoroughly when designing biomaterials. There is considerable renewed interest in silver nanoparticles (AgNPs) owing to their ability to potentiate antibacterial properties against multiple bacterial strains. This study aimed to develop two antibacterial bone regenerative scaffolds by integrating AgNPs in bovine bone particles (BBX) (Product 1), and a light cross‐linked hydrogel GelMA (Product 2). The constructs were characterized using scanning electron microscopy. Metabolic activity of osteoblasts and osteoclasts on the constructs was investigated using PrestoBlue™. Disk diffusion assay was conducted to test the antibacterial properties. The regenerative capacity of the optimized AgNP functionalized BBX and GelMA were tested in a rabbit cranial 6 mm defect model. The presence of AgNPs appears to enhance proliferation of osteoblasts compared to AgNP free controls in vitro. We established that AgNPs can be used at a 100 μg dose that inhibits bacteria, with minimal adverse effects on the bone cells. Our rabbit model revealed that both the BBX and GelMA hydrogels loaded AgNPs were biocompatible with no signs of necrosis or inflammatory response. Grafts functionalized with AgNPs can provide antibacterial protection and simultaneously act as a scaffold for attachment of bone cells. [ABSTRACT FROM AUTHOR]

A multifunctional nanostructured hybrid composed of metal–protein–ceramic was designed and then synthesized using three different methods: chemical reduction, physical adsorption, and coprecipitation. The processes yielded colloidal spherical silver nanoparticles (AgNPs) enveloped in a bovine serum albumin (BSA) corona, leading to the core–shell structure AgNPs–BSA. To enhance biocompatibility and mitigate potential toxicity associated with metallic nanoparticles, this core–shell structure was coated with a layer of calcium carbonate (CaCO3). In order to analyze the internal structure of the resulting hybrid nanostructure (AgNPs–BSA–CaCO3), a number of samples were produced by focused ion beam (FIB) and characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and zeta potential (ζ) measurements. The cytotoxic effect of the samples were evaluated through in vitro tests on mouse macrophage cell line RAW 264.7 ATCC TIB‐71, this was accomplished by calculating the appropriate concentrations from the dose–response curve of AgNPs. Research showed that the AgNPs–BSA–CaCO3 mixture triggered the formation of vaterite; these findings were corroborated by FTIR and Raman techniques. The spherical nanostructures have an average diameter size of 4.3 ± 2 μm and an average roughness (Ra) of 3.11 ± 0.62 μm. Zeta potential (ζ) and isoelectric point studies reveal that this hybrid nanostructure exhibits amphoteric behavior that differs from either AgNPs or AgNPs–BSA alone. Cell viability response exceeded 75%, indicating the noncytotoxic nature of the proposed hybrid nanostructures. [ABSTRACT FROM AUTHOR]

The association of silver nanoparticles (AgNps) to sealant agent Palaseal® can be a promising alternative for complete denture wearers who may develop denture stomatitis (DS). The study aimed to evaluate the anti-Candida and biocompatible potential of silver nanoparticles synthesized by three routes associated with denture glaze to prevent and/or treat oral candidiasis. Surface acrylic resin specimens were treated with different associations of glaze with AgNps (VER+AgUV, VER+AgTurk and VER+AgGm). As controls, specimens were treated with glaze+nystatin (VER+Nyst), glaze only (VER) or submerged in PBS (PBS). Afterwards, Candida albicans biofilm was developed for 24 h, 15 d and 30 d. Subsequently, the biofilm was quantified by CFU/mL, XTT assay and confocal laser scanning microscopy. Fibroblasts were submitted to conditioned medium with the same associations for 24, 48 and 72 h and LIVE/DEAD® viability test was carried out. Regardless of the period, there was a significant reduction (p < 0.01) of viable fungal cells load, as well as inhibition of fungal metabolic activity, in specimens treated with glaze+AgNps associations, compared to VER and PBS. The anti-Candida effects of the associations were similar to the VER+Nyst group, with emphasis on VER+AgGm, which showed the highest percentage values of non-viable fungal cells maintained over time. The associations did not prove toxicity to fibroblasts. The AgNps exerted antimicrobial activity against C. albicans biofilms and are biocompatible. The most effective results were achieved with the association of glaze+silver nanoparticles synthesized by the green chemistry method (AgGm), proving to be an innovative alternative in the management of DS. [ABSTRACT FROM AUTHOR]

Helminths are considered a significant threat to the livestock industry, as they cause substantial economic losses in small and large ruminant farming. Their morbidity and mortality rates are also increasing day by day as they have zoonotic importance. Anthelmintic drugs have been used for controlling these parasites; unfortunately, due to the development of resistance of these drugs in helminths (parasites), especially in three major classes like benzimidazoles, nicotinic agonists, and macrocyclic lactones, their use is becoming very low. Although new anthelmintics are being developed, the process is time-consuming and costly. As a result, nanoparticles are being explored as an alternative to anthelmintics. Nanoparticles enhance drug effectiveness, drug delivery, and target specificity and have no resistance against parasites. Different types of nanoparticles are used, such as organic (chitosan) and inorganic (gold, silver, zinc oxide, iron oxide, and nickel oxide). One of them, silver nanoparticles (AgNPs), has unique properties in various fields, especially parasitology. AgNPs are synthesized from three primary methods: physical, chemical, and biological. Their primary mechanism of action is causing stress through the production of ROS that destroys cells, organs, proteins, and DNA parasites. The present review is about AgNPs, their mode of action, and their role in controlling anthelmintic resistance against small and large ruminants. [ABSTRACT FROM AUTHOR]

Green nanomaterial synthesis is the process of producing various metallic nanoparticles (MNPs) utilizing bioactive reagents. It attempts to reduce waste and promote environmental sustainability by employing mild reaction conditions and safe materials. Researchers have demonstrated a strong interest in using natural biomolecules extracted from plants to synthesize MNPs. The individual biomolecules in this plant extract function as reducing, capping, and stabilizing substances in the green production of stable MNPs using their related metal ion precursor solution. The advantages of this method are that it is environmentally friendly, does not require energy, and is cheap and quick. Recently, MNPs have been developed in the field of cancer due to various qualities, including their increased reactive surfaces and small specified volume, which make them suited for traditional small pharmaceuticals and pharmaceutical compounds. MNPs, such as gold (AuNPs), silver (AgNPs) and copper (CuNPs), are increasingly being used as anticancer agents. This review describes the synthesis of three MNPs: AuNPs, AgNPs and CuNPs nanoparticles from plant extracts. AgNPs are the most often used synthetic NPs, accounting for more than 25% of all consumer items. AgNPs are generally employed for antibacterial, antifungal and antiviral purposes. Also, the anti-cancer activities of the MNPs were explained. The challenges and predicted developments for future studies are addressed, which are critical for real-world applications. In the future, new types of NPs will be generated employing modern technology, with a wide range of uses in numerous industries. [ABSTRACT FROM AUTHOR]

Nanotechnology has been a central focus of scientific investigation over the past decades owing to its versatile applications. The synthesis of silver nanoparticles (AgNPs) through plant secondary metabolites is a cost-effective and eco-friendly approach. The present study employed Brassica carinata microgreen extracts (BCME) to promote the reduction of silver nitrate (AgNO3) salt into Brassica carinata microgreen silver nanoparticles (BCM-AgNPs). The physicochemical properties of the biosynthesized AgNPs were characterized through both spectroscopy and microscopy techniques. Furthermore, the antimicrobial property of the biosynthesized AgNPs was assessed against six selected pathogenic microorganisms, and finally, their safety was evaluated on a normal Vero cell line through an MTT cytotoxicity assay. The UV-visible spectrum revealed that BCM-AgNPs exhibited an absorption peak at 420 nm. The potential functional groups involved in the biosynthesis of AgNPs were identified by Fourier transform infrared (FTIR) analysis. Scanning electron microscopy (SEM) revealed a spherical nature of the biosynthesized AgNPs. Transmission electron microscopy (TEM) analysis revealed the crystallinity of the AgNPs, averaging 34.68 nm in size. X-ray diffraction (XRD) investigation further confirmed the crystalline structure of the AgNPs. The zeta potential exhibited a significant value of − 22.5 ± 1.16 mV. Regarding the antimicrobial potential, BCM-AgNPs exhibited promising antimicrobial activity against the tested pathogens, with a minimum inhibitory concentration (MIC) of 62.5 µg/mL observed in Pseudomonas aeruginosa. Further cytotoxicity assessment of BCM-AgNPs conducted on Vero cells demonstrated their safety. This study presents a novel approach to synthesizing AgNPs using a nutraceutical microgreen, offering a biocompatible and promising alternative for combating multi-drug resistance. [ABSTRACT FROM AUTHOR]

Highlights In this study, epoxy based piezoelectric polymer composites were fabricated using two different curing agents and varying compositions of poly(vinylidene) fluoride (PVDF), barium titanate (BaTiO3), and conductive silver nanoparticles. The effect of piezoelectric ceramic and conductive nanofillers on enhancing the PVDF β phase within the composite structure was investigated. Structural, thermal, and morphological characterizations of the polymer composites were performed using x‐ray diffraction, differential scanning calorimetry, and scanning electron microscopy. Furthermore, a comprehensive analysis of mechanical properties and fracture toughness was conducted in addition to the piezoelectric behavior. A voltage output of 1.35 V was generated by a polymer composite containing 20 wt% BaTiO3, with a Young's modulus of 2 GPa and a fracture energy of 2.3 kJ/m2. The findings of this study contribute to expanding the knowledge and understanding of piezoelectric polymer composites, enabling their potential utilization in various scientific and technological applications. Enhancing mechanical and piezoelectric properties of epoxy based piezoelectric composites. A clear and comprehensive description of the experimental procedures employed. Comparative analysis methods: structural, thermal, mechanical, fracture, and piezoelectric property analyses. [ABSTRACT FROM AUTHOR]

The fabrication of reusable SERS substrates with sensitivity at the single‐molecule level remains challenging but promising. Herein, a composite surface‐enhanced Raman scattering (SERS) substrate is proposed that includes Ag nanoparticle (Ag NPs) /Graphene/BaTiO3 (Ag/G/BTO) from a chemical enhancement perspective. The pyroelectric field generated by BaTiO3 drives the charge transfer between the SERS substrate and molecules, achieving a significant improvement in the SERS performance and self‐cleaning properties. The SERS signals of rhodamine 6G (R6G) molecules are further amplified up to 70‐fold. Thus, the detection limit is reduced by three orders of magnitude in this study, reaching 10−14 m after applying a pyroelectric field. In addition, the substrate exhibits a higher degradation efficiency than previous self‐cleaning SERS substrates because of the outstanding catalytic properties of BaTiO3. Target molecules are degraded effectively after several temperature cycles. A detailed mechanism analysis of pyroelectric SERS is conducted based on theoretical simulations and experimental results. This study is considered to deepen the understanding of SERS mechanisms and boost the application of SERS technology. [ABSTRACT FROM AUTHOR]

This paper presents the results of studies on the effects of four types of aerosols containing an aqueous dispersed suspension of graphene oxide (GO) and an aqueous dispersed suspension of graphene oxide with the addition of curcumin (GO + C), silver nanoparticles (GO + Ag), and hypochlorous acid (GO + HClO) on selected structural and biological properties. Structural studies were carried out using electron microscopy, including a scanning electron microscope (SEM), scanning transmission electron microscopy (STEM), laser emission spectroscopy (LIBS), and absorption spectra in the infrared range attuned total reflectance (FTIR-ATR). The growth inhibition zone and viability of Staphylococcus aureus and Pseudomonas aeruginosa bacteria were studied. Studies have shown that the addition of silver nanoparticles and hypochlorous acid to the nanostructures of graphene oxide suspension improves bactericidal properties. In addition, it was observed that the application of a dispersed graphene oxide suspension in the form of an aerosol enriched with hypochlorous acid and silver nanoparticles results in the formation of a fairly uniform layer of graphene flakes, characterized by the presence of admixtures used. [ABSTRACT FROM AUTHOR]

This study reveals one-step green synthesis of plant inspired silver nanoparticles (Ag-NPs). The synthesis procedure relies on the bio-reduction of Ag+ to Ag0 using orange waste (orange peel) extract as cheap, readily available, sustainable, biocompatible feedstocks as a reducing and stabilizing agent. The prepared Ag-NPs passed through a full characterization procedure for better confirmation and elucidation of optical and structural properties. The fluorescence of the prepared Ag-NPs has a quantum yield of 17.15% enabling its potential use in chemical sensing of drugs. Ag-NPs are conceived to be used as a fluorescent nano sensor for sensitive, ecofriendly, rapid spectrofluorimetric determination of two recent direct oral anticoagulants, namely, rivaroxaban (RIV) and edoxaban tosylate monohydrate (EDT); COVID-19 adjunctive drugs in their raw materials and pharmaceutical tablets. The fluorescence of the prepared Ag-NPs at 333 nm (λ ex = 258 nm) was found to be substantially quenched in existence of increasing concentrations of each drug. The quenching mechanisms were studied and explained. The validation of the method revealed linear correlation over the ranges of 0.5–10 µg/ml with an excellent regression correlation (r = 0.9999) for both drugs with minimum detection limits of 0.14 and 0.16 µg/ml for rivaroxaban and edoxaban tosylate monohydrate, correspondingly. Three different metrics were employed for verifying the greenness profile of the presented study. The findings of the greenness assessment were congruent and compatible with the green synthesis procedure, ecofriendly analysis, and the exclusion of using organic solvents and noxious materials opening an avenue for green synthesis of nanoparticles instead of chemical and physical methods. [ABSTRACT FROM AUTHOR]