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Surface-enhanced Raman scattering (SERS) is highly dependent on the adsorption of target molecules onto metallic surfaces, such as colloidal metallic nanoparticles. The selection of suitable substrates is crucial for optimizing SERS performance. Herein, we investigated the dependence of two pesticide SERS signals, thiabendazole (TBZ) and carbendazim (MBC), on both Ag nanoparticles (reduced by hydroxylamine—AgH or citrate—AgCT) and the aggregation conditions induced by adding different salts (NaCl, KCl or KNO3). In addition to SERS experiments, in order to assess the induced aggregation of the Ag nanoparticles, UV-Vis absorption spectroscopy, dynamic light scattering (DLS) and zeta potential were employed. For AgH, the use of salts did not yield the greatest effect in the presence of TBZ, as only with the pesticide was it possible to achieve the highest aggregation and greater intensity of the SERS signal. In contrast, with the MBC pesticide, the KNO3 salt promoted the greatest aggregation state and was crucial for obtaining the most amplified SERS signal. The thicker coating layer of AgCT prevented the adsorption of both pesticides on the surface of the nanoparticles, which was achievable using salts containing Cl− ions. Additionally, to obtain the SERS signal of MBC with AgCT, besides the presence of chlorinated salts, other adjustments were necessary, such as changing both the pH of the medium (from pH 5.8 to pH 8, for which MBC is in its neutral form) and the laser lines (from 785 to 514.5 nm). These findings demonstrated that although the pesticide molecules belong to the same chemical functional group, their detection was strongly influenced by the surface of the silver nanoparticles and the salts added. This highlights the specific nuances in detection depending on the method of Ag synthesis and the nature of the aggregating agents used. [ABSTRACT FROM AUTHOR]

Nanocomposites based on metal nanoparticles (MNP) prepared with mangosteen (mgt) peel extract-mediated biosynthesis of Agmgt/Znmgt have attracted considerable interest due to their potential for various practical applications. In this study, their role in developing antibacterial protection for rubber cotton gloves is investigated. The process of mangosteen-peel-extract-mediated biosynthesis produced Agmgt/Znmgt nanocomposites with respective diameters of 23.84 ± 4.08 nm and 30.99 ± 5.73 nm, which were assessed in the context of antimicrobial rubber-coated gloves. The rubber glover surface exhibited a very dense deposition of the Ag+Znmgt nanocomposite, which subsequently demonstrated level 4 resistance to punctures under the ANSI-ISEA 105-2016 standard. This could be attributed to the Zn-cellulose double formation on the rubber surface. Notably, on testing the inhibition of bacterial growth, the extract with the Agmgt nanoparticles presented the least concentration capable of growth inhibition in comparison to the extracts with Znmgt and Ag+Znmgt nanoparticles. Each of the mangosteen extracts was shown to inhibit bacterial growth when tested against both Gram-positive cocci and Gram-negative bacilli, with MIC in the range 40–320 µg/mL. The growth of drug-resistant bacteria (MRSA) could also be inhibited with an MIC value of 160 µg/mL, and with 30 min of contact, gloves with respective coatings of Znmgt and Ag+Znmgt extract nanocomposites were shown to inhibit K. pneumoniae and MRSA. However, while effective bacterial inhibition occurred with the suspensions, the coatings on glove surfaces required a lengthy incubation period (contact time) of at least 30 min for efficacy. [ABSTRACT FROM AUTHOR]

For ensuring the economic feasibility of the electrochemical carbon dioxide reduction reaction (CO2RR), which can be used to reduce the catalyst load and increase the catalytic activity of CO2RR by using carrier materials. Here, we report the systematic alteration of metal chloride on bipyridine groups in MOF‐253(Al) using modified metal–organic frameworks (MOFs) as precursors and the introduction of Ag nanoparticles to prepare catalysts Ag@M‐N/Al‐O (M = Co, Ni, Zn, Cu). EDS spectra showed the uniform dispersion of Ag nanoparticles. In addition, the chemical structure of the catalyst was analyzed by XPS and PXRD, which proved the existence of M‐N and Al‐O bonds. The interaction with Ag nanoparticles leads to electron density reconstruction, and the stable *COOH intermediates with electron delocalization enhanced by polymetallic electron configuration modulation are conducive to CO production. The results show that Ag@Co‐N/Al‐O can achieve 85.6% FE for CO and has good stability within 12 h. This work provides a new idea for CO2RR material design using MOFs as a precursor catalyst. [ABSTRACT FROM AUTHOR]

The increasing emergence of antibiotic-resistant bacteria and the need to reduce the use of antibiotics call for the development of safe alternatives, such as silver nanoparticles. However, their potential cytotoxic effect needs to be addressed. Graphene oxide provides a large platform that can increase the effectiveness and safety of silver nanoparticles. Graphene oxide and silver nanoparticles complex applied as a part of an innovative material might have direct contact with human tissues, such as skin, or might be inhaled from aerosol or exfoliated pieces of the complex. Thereby, the safety of the prepared complex has to be evaluated carefully, employing a range of methods. We demonstrated the high cytocompatibility of graphene oxide and the graphene oxide–silver nanoparticles complex toward human cell lines, fetal foreskin fibroblasts (HFFF2), and lung epithelial cells (A549). The supporting platform of graphene oxide also neutralized the slight toxicity of bare silver nanoparticles. Finally, in studies on Staphylococcus aureus and Pseudomonas aeruginosa, the number of bacteria reduction was observed after incubation with silver nanoparticles and the graphene oxide–silver nanoparticles complex. Our findings confirm the possibility of employing a graphene oxide–silver nanoparticles complex as a safe agent with reduced silver nanoparticles' cytotoxicity and antibacterial properties. [ABSTRACT FROM AUTHOR]

In recent years, the synthesis of silver nanoparticles (Ag NPs) has garnered significant interest due to their unique structural and optical properties. Pulsed laser ablation in liquid (PLAL) has emerged as an environmentally friendly, efficient, and remotely controllable method for fabricating metallic nanoparticles. In this study, we investigated the effect of confinement geometry on the optical and structural properties of Ag NPs produced by PLAL. Ag NPs were synthesized under different geometric boundary conditions and characterized using a range of techniques. Photoluminescence spectroscopy revealed that an increase in particle size led to a decrease in intensity due to carrier recombination, with the emission peak detected at approximately 350 nm when subjected to laser excitation at 250 nm. UV–Vis spectroscopy showed that the surface plasmon resonance (SPR) wavelength of Ag NPs synthesized without confined geometry was located at 400 nm, in agreement with the literature. We found that increasing the size of the confined geometry resulted in a higher SPR peak intensity and peak position. X-ray diffraction (XRD) analysis confirmed that all samples (Ag, Ag–dAl confine geometry) were polycrystalline. High-resolution transmission electron microscopy (HR-TEM) revealed a small size distribution of spherical particles with an average size of 9.6 nm, as determined by lognormal fitting measurement. Fourier transform infrared (FTIR) spectroscopy confirmed the purity of the synthesized Ag NPs. Our findings demonstrate that confinement geometry plays a crucial role in controlling the optical and structural properties of Ag NPs synthesized by PLAL, making it a promising approach for producing high-quality Ag NPs for various applications. [ABSTRACT FROM AUTHOR]

The drive for the development of systems that can simultaneously investigate chemical and morphological information comes from the requisite to fully understand the structure and chemical reactivity relationships of materials. This is particularly relevant in photocatalysis, a field ruled by surface interactions. An in-depth understanding of these complex interactions could lead to significant improvements in materials design, and consequently, in photocatalytic performances. Here, we present a first approach to a combined atomic force microscopy (AFM) and Raman spectroscopy characterization of anodic TiO2 nanotubes arrays decorated with Ag nanoparticle electrodeposition from either the same anodizing organic electrolyte or from an aqueous one. Photocatalytic substrates were used in up to 15 consecutive photocatalysis tests to prove their possible deterioration with reuse. Sample aging can, in principle, produce changes in both the morphology and the chemical compounds that characterize the photocatalyst surface. Adopting multiple characterization techniques, such as a combination of AFM and Raman spectroscopy in an original setup, can profitably enable the observation of surface contamination. A significant drop in photocatalytic activity was observed after 10 cycles on samples where silver was deposited from the organic electrolyte, while the others remained stable. Such a drop was ascribed to photocatalyst deactivation. While in other cases, a simple recovery treatment allowed the initial photoactivity to be restored, this deactivation was not restored even after chemical and thermal cleaning treatments. [ABSTRACT FROM AUTHOR]

Plasmonic nanoparticles exhibit remarkable photothermal properties, making them valuable in various fields such as renewable energy and medicine. These photothermal properties depend on several factors, including the type of noble metal, particle size, and the stabilizing layer. This study investigates the photothermal properties of colloidal silver nanoparticles synthesized photochemically using UV LEDs. Silver nanoparticles capped with citrate and a combination of citrate and polyvinylpyrrolidone (PVP) were prepared. While the nanoparticle size remained unaffected by the amount of citrate, the nonlinear refractive index did show dependence. As the citrate concentration increased, the nonlinear refractive index decreased. Additionally, increasing the amount of PVP not only reduces the nanoparticle size—suggesting a reverse Ostwald ripening process induced by UV light—but also leads to a diminished photothermal response. [ABSTRACT FROM AUTHOR]

Plasmonic nanoparticles exhibit remarkable photothermal properties, making them valuable in various fields such as renewable energy and medicine. These photothermal properties depend on several factors, including the type of noble metal, particle size, and the stabilizing layer. This study investigates the photothermal properties of colloidal silver nanoparticles synthesized photochemically using UV LEDs. Silver nanoparticles capped with citrate and a combination of citrate and polyvinylpyrrolidone (PVP) were prepared. While the nanoparticle size remained unaffected by the amount of citrate, the nonlinear refractive index did show dependence. As the citrate concentration increased, the nonlinear refractive index decreased. Additionally, increasing the amount of PVP not only reduces the nanoparticle size—suggesting a reverse Ostwald ripening process induced by UV light—but also leads to a diminished photothermal response. [ABSTRACT FROM AUTHOR]

The photoreduction method was utilized to synthesize the Ag/PW12/g-C3N4 nanocomposite. The polyanion PW12O403− served as the photoreductant, and as a stabilizer and protectant for Ag nanoparticles. TEM images reveals that Ag nanoparticles with a size of approximately 5 nm were modified on the surface of g-C3N4. Photocatalytic experiments confirm that Ag/PW12/g-C3N4, with the mass ratio of Ag3PW12O40 to g-C3N4 nanosheets at 30%, exhibits high efficiency and durability in the photodegradation of Rhodamine B. Research on the photocatalytic mechanism indicates that decorating PW12O403− and Ag nanoparticles on the surface of g-C3N4 nanosheets is beneficial for improving the separation of electron–hole pairs and enhancing the capability for visible light absorption. [ABSTRACT FROM AUTHOR]

Magnetic molecularly imprinted polymers (MMIPs) are used as artificial antibody materials. MMIPs have attracted a great deal of interest because of their low cost, wide practicality, predetermination, stability and their ability to achieve rapid separation from complex sample environments by the action of external magnetic field. MMIPs can simulate the natural recognition of entities. They are widely used because of their great advantages in terms of high selectivity. In this review article, the preparation methods of Fe3O4 NPs and a detailed summary of the commonly used methods for amination modification of Fe3O4 NPs are introduced, preparation of Ag NPs of different sizes and Au NPs of various shapes and preparation methods of magnetic molecularly imprinted plasmonic SERS composite nanoparticles such as Fe3O4@Ag NPs, Fe3O4/Ag NPs, Fe3O4@Au NPs, Fe3O4/Au NPs, Fe3O4@Au/Ag NPs and Fe3O4@Ag@Au NPs are main summarized. In addition, preparation process and the current application of MMIPs prepared from magnetic molecularly imprinted plasmonic SERS composite nanoparticles incorporating different functional monomers in a nuclear-satellite structure are also presented. Finally, the existing challenges and future prospects of MMIPs in applications are discussed. [ABSTRACT FROM AUTHOR]

Today, hydrogel dressings that can protect injury sites and effectively promote healing have become highly desirable in wound management. Therefore, multifunctional silver-poli(N-isopropylacrylamide/itaconic acid) (Ag-P(NiPAAm/IA)) hydrogel nanocomposites were developed for potential application as topical treatment dressings. The radiolytic method, used for the crosslinking of the polymer matrix as well as for the in situ incorporation of silver nanoparticles (AgNPs) into the polymer matrix, enables the preparation of hydrogel nanocomposites without introducing harmful and toxic agents. Moreover, materials produced using γ-irradiation are simultaneously sterilized, thus fulfilling one of the basic requirements regarding their potential biomedical applications. The NiPAAm/IA ratio and the presence of AgNPs influenced the microstructural parameters of the investigated systems. Increasing the IA content leads to the formation of a more porous polymer matrix with larger pores, while the incorporated AgNPs act as additional junction points, decreasing the porosity and pore size of the resulting nanocomposite hydrogels. Swelling studies showed that most investigated systems uptake the fluids from their surroundings by non-Fick diffusion. Further, the Ag+ ion release, antibacterial activity, and cytotoxicity of Ag-P(NiPAAm/IA) hydrogel nanocomposites were examined to evaluate their biomedical potential. All hydrogel nanocomposites showed an initial burst release of Ag+ ions (useful in preventing bacteria adherence and biofilm formation), followed by a slower release of the same (ensuring sterility for longer use). An antibacterial activity test against Escherichia coli and Staphylococcus aureus showed that Ag-P(NiPAAm/IA) hydrogel nanocomposites, with silver concentrations around 10 ± 1 ppm, successfully prevent bacterial growth. Finally, it was shown that the investigated hydrogel nanocomposites do not exhibit a cytotoxic effect on human keratinocyte HaCaT cells. Therefore, these multifunctional hydrogel nanocomposites may promote wound repair and show promising potential for application as functional wound dressing. [ABSTRACT FROM AUTHOR]

A novel fluorescent sensor based on silver nanoparticle-carbon dot composites (Ag@CDs) has been developed for the rapid and quantitative detection of aquatic bacteria. The sensor operates on the principle of plasmon-enhanced resonance energy transfer, where the fluorescence of CDs is quenched by Ag nanoparticles and restored upon bacterial interaction due to the generation of reactive oxygen species. The Ag@CDs exhibit a linear response to bacterial concentration over the range 7 × 104 ~ 4 × 107 CFU·mL−1, with a low detection limit of 4 × 104 CFU·mL−1. The fluorescence recovery is rapid, reaching maximum intensity within 5 min. The method demonstrates high selectivity, with minimal interference from common ions and compounds found in municipal and industrial wastewater. The Ag@CDs-based 96-well plate assay for quantitative measurement of bacteria was developed. The assay's performance was further validated through the analysis of real water samples, showing a recovery of 94.0 ~ 102% for domestic wastewater and 97.6 ~ 106% for industrial wastewater. Also, Ag@CDs-based test strips assay for semi-quantitation were developed for rapid in-field aquatic bacteria detection. Ag@CDs can be conveniently integrated into 96-well plates and test strips, providing rapid on-site aquatic bacteria testing. [ABSTRACT FROM AUTHOR]

Titanium alloys are among the widely used biomedical materials due to their biocompatibility and mechanical performance. It is an indisputable fact that the materials used in this area must be antibacterial. Therefore, in this study, the production of antibacterial Titanium alloys using NanoAg particles for use in biomedical applications was investigated. First, Ti-6Al-4 V titanium alloys were produced by the powder metallurgy method, which includes blending, pressing and sintering processes. Nano silver particles were synthesized by a chemical reduction method using silver nitrate and glucose. The resulting solution was subjected to Ag + ions and glucose determinations, pH and turbidity analysis. Nano Ag application was carried out by two different methods; dipping and coating method. The obtained samples were analyzed by scanning electron microscopy (SEM) and optical microscopy. Additionally, as the main purpose of this study, antibacterial analysis against Escherichia Coli and Staphylococcus Aureus was performed by percentage reduction test. While the coating method was seen to be more successful in antibacterial tests, the overall Nano Ag application performance was found to be higher against Escherichia Coli bacteria. Being that the sample containing 5% Nano Ag titanium alloys produced with the coating technique showed 100% killing effect against both Staphylococcus aureus and Escherichia coli. [ABSTRACT FROM AUTHOR]

Flexible hybrid heterojunction solar cells (HHSCs) utilizing a heterojunction of thin, flexible silicon (Si) with poly-(3,4-ethylenedioxythiophene):poly-(styrenesulfonate) (PEDOT:PSS) are quite promising owing to their lightweight, cost-effectiveness, simple device design, low-temperature fabrication, and notable performances. However, effective light harvesting for thin Si without surface nano/microstructuring and poor charge transport properties of the polymer are pressing issues for efficient flexible HHSCs. Here, plasmonic silver nanoparticles (Ag NPs) of ∼30 nm diameter are introduced into the PEDOT:PSS matrix to overcome such challenges. The Ag NPs are synthesized by a cost-effective, simple chemical reduction approach (Turkevich method). The role of Ag NPs on the fabrication and performance of ≤50 μm thin, flexible Si-based HHSCs has been investigated as a function of Ag NP concentration. The incorporation of 0.75 wt % in PEDOT:PSS led to ∼21% enhancement in the power conversion efficiency without any additional surface structuring of Si. Enhanced light trapping, electrical conductivity of the polymer layer, and charge carrier transport, facilitated by the Ag NPs in the polymer matrix, are attributes of the device performance. The mechanism of improved light trapping is explained via the fascinating plasmonic properties of Ag NPs. The electrical conductivity of the Ag NPs and PEDOT:PSS matrix is explained by improved charge transfer in the polymer. Such a concept, which can avoid conventional surface micro/nanostructuring steps for flexible Si-based solar cells, has not been explored yet and holds immense potential to enhance performance. [ABSTRACT FROM AUTHOR]

We prepared novel plasmon-coupled silver (Ag) and silver oxide (Ag2O) nanoparticles using green synthesis and a magnetic stirrer device from lemon juice. Firstly, we prepared six Ag samples from green tea and lemon juice, characterized by XRD, FTIR, UV, and HRTEM. We selected just two samples to apply to MDA-MB-231 cells. The samples entered the cell through endocytosis, showed moderate cytotoxicity and ROS levels, caused cell growth arrest at the G2M phase, exhibited higher inhibition of Cyclin D1, and induced early apoptosis. β-Catenin is an abundant protein in triple-negative breast cancer TNBC. Both samples showed inhibition of the β-catenin proteins pathway. Plasmon-coupled nanoparticles effectively inhibited β-catenin, physically capturing β-catenin and its pathway proteins, mimicking the action of a degradation protein complex due to their geometric properties. The prepared materials could be considered a promising treatment for TNBC that has not responded to chemotherapy and radiotherapy. As they have low toxicity to normal cells; this paves the way for new material designs without strict size limitations. [ABSTRACT FROM AUTHOR]

The current world is exposed to immense classes of challenges, of which antimicrobial-caused infectious diseases have been ranked the third killer disease due to their high resistance capability. Oxidative stress is also the other problem faced by the current world. In the current study, a leaf of Foeniculum Vulgare was employed for the synthesis of silver nanoparticles (Ag NPs) within the 1:3, 1:1, and 3:1 compositions using 0.1 M of AgNO3. The calculated average crystalline size from X-ray diffraction (XRD) was found to be 12.6, 13.7, and 21.6 nm for the 1:3, 1:1, and 3:1 volume ratios, respectively. Scanning electron microscope coupled with energy dispersive spectroscopy (SEM-EDS) analysis depicts the quasi-spherical shape with an intense Ag peak at around 3.00 eV. Transmission electron microscope coupled with high-resolution transmission microscope with surface area electron diffraction pattern (TEM-HRTEM with SAED) showed spherical shaped Ag NPs. The electronic bandgap energy was calculated as 3.1, 3.2, and 3.3 eV for the 1:1, 3:1, and 1:3 volume compositions, respectively. Ag NPs show 13.5, 12.5, and 11.0 mm zones of inhibition for the 1:3, 1:1, and 3:1 ratios, respectively. The antifungal activity was found to be 16.9, 11.2, and 10.5 mm for the 3:1, 1:3 and 1:1 ratios, respectively. Lastly, the antioxidant activity was estimated to be 42.4, 28.94, and 27.39% RSA for the 1:1, 3:1, and 1:3 volume ratios respectively. All the ratios of Ag NPs showed promised antimicrobial and antioxidant activity in the presence of 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) due to the enhanced generation of reactive oxygen species (ROS). Highlights: Green Synthesis of Ag NPs within three volume ratios in the presence of Foeniculum vulgare leaf extract. Investigating the potential antibacterial, antifungal, and antioxidant activities. Comparative study of the volume ratios on the antimicrobial and antioxidant activities. [ABSTRACT FROM AUTHOR]

Furfural is an essential compound that contributes to the distinctive flavor of sauce-flavored Baijiu. However, traditional detection methods are hindered by lengthy and complex sample preparation procedures, as well as the need for expensive equipment. Therefore, there is an urgent need for a new approach that allows rapid detection. In this study, we developed a novel surface-enhanced Raman spectroscopy (SERS) substrate by constructing MXene (Ti3C2TX) @Ag nanoparticles (Ag NPs) through an electrostatic attraction method. The MXene (Ti3C2TX) @Ag NPs were successfully fabricated, with adsorbed NaCl-treated Ag NPs uniformly absorbed on the surface of MXene (Ti3C2TX), creating high-density distributed SERS "hot spots". The prepared substrate demonstrated excellent sensitivity, uniformity, repeatability, and long-term stability, with a low detectable concentration of 10−9 M for R6G (Rhodamine 6G) and an enhancement factor of up to 7.08 × 105. When applied for the in situ SERS detection of furfural in Baijiu, the detection limit was as low as 0.5 mg/L. Overall, the proposed method offers rapid, low-cost, and sensitive quantitative analysis, which is significant not only for detecting furfural in Baijiu but also for identifying hazardous substances and distinguishing between authentic and counterfeit Baijiu products. [ABSTRACT FROM AUTHOR]

The aim of presented study was to test nutritional properties of potato tubers and silver ions accumulation pattern after foliar application of silver nanoparticles (AgNPs) during potato vegetation. Potato plants were sprayed with different concentration of Ag nanoparticles (0.1, 1.0 and 10 mg·dm−3) synthesized with incorporation with sodium dodecyl sulphate (SDS) and sodium citrate as stabilizing agent. The lowest amounts of silver ions were transported to the tubers after spraying with AgNPs synthesized with SDS, rather than with citrate. Nevertheless silver ions accumulation in tubers was negligible. SDS method of synthesis was more favourable in terms of nutritional properties of potato tubers. The highest tested concentration of AgNPs_SDS had a favourable effect on a variety of macro- and micronutrients, ascorbic acid and soluble sugars. In turn, lower concentrations of AgNPs_SDS increased the content of phenolic compounds and free radical scavenging efficiency of tubers. These correlations were also confirmed by Principal Component Analysis. [ABSTRACT FROM AUTHOR]

Green synthesis represents a superior strategy for mitigating the adverse effects of chemical synthesis on the environment. In particular, the utilization of bio-sourced materials for nanomaterial synthesis constitutes a more sustainable and environmentally sound alternative. In this study, silver–carbon particle (Ag-CP) nanocomposites were prepared by a green hydrothermal method using lily bulbs as raw materials and were employed for glucose detection. Through the use of various physical characterization techniques, it was demonstrated that the natural lily hydrothermal method yielded carbon particles that were modified with Ag nanoparticles. The electrochemical characteristics of the Ag-CP nanocomposites for glucose sensing were investigated using cyclic voltammetry and chronoamperometry. The results showed that the constructed glucose sensor was capable of detecting concentrations within the range of 1–11 mM (R2 = 0.998), with sensitivity of 203.56 μA mM−1 cm−2 and a detection limit of 76.6 μM (S/N = 3). The Ag-CP nanocomposite sensor also exhibited notable electrocatalytic activity and remarkable anti-interference capability. In light of the exceptional sensing performance, coupled with the straightforward and cost-effective preparation process, the development of nanocomposite materials employing naturally sourced biological materials represents an attractive avenue for the production of eco-friendly nanocomposites. [ABSTRACT FROM AUTHOR]

Surface-Enhanced Raman Spectroscopy (SERS) is a powerful, non-destructive technique for enhancing molecular spectra, first discovered in 1974. This study investigates the enhancement of Raman signals from single- and few-layer molybdenum disulfide (MoS2) when interacting with silver nanoparticles. We synthesized a MoS2 membrane primarily consisting of monolayers and bilayers through a wet chemical vapor deposition method using metal salts. The silver nanoparticles were either directly grown on the MoS2 membrane or placed beneath it. Raman measurements revealed a significant increase in signal intensity from the MoS2 membrane on the silver nanoparticles, attributed to localized surface plasmon resonances that facilitate SERS. Our results indicate that dichalcogenide/plasmonic systems have promising applications in the semiconductor industry. [ABSTRACT FROM AUTHOR]

A series of Ag-TiO2 nanotube catalysts were prepared by electrochemical deposition. Doping of Ag nanoparticles was regulated by adjusting the deposition voltage, which altered the photocatalytic performance of the sample. The electrochemical properties of the Ag-TiO2 nanotubes were characterized using X-ray photoelectron spectroscopy, scanning electron microscopy (SEM), photoluminescence (PL) spectroscopy, and ultraviolet–visible (UV–vis) diffuse reflection spectroscopy. PL and UV–vis spectroscopy showed that the Ag-TiO2 nanotubes had a higher visible-light absorption activity and a lower photogenerated electron–hole pair recombination rate. SEM analysis showed that the highly ordered tubular structure of the TiO2 nanotubes was not disrupted after electrochemical deposition, and the size and quantity of the Ag nanoparticles deposited on the TiO2 nanotubes increased with increasing deposition voltage. The Ag-TiO2 nanotubes prepared at a deposition voltage of 1 V exhibited the highest hydrogen evolution efficiency, with a theoretical hydrogen production rate of 12.59 µmol∙cm−2∙h−1 under UV irradiation. This was 2.1-fold higher than that of pure TiO2 nanotubes and was attributable to the local surface plasmon resonance effect of Ag nanoparticles, which enhanced the visible light absorption by the TiO2 nanotubes. [ABSTRACT FROM AUTHOR]

The increasing threat from antibiotic-resistant bacteria has necessitated the development of novel methods to counter bacterial infections. In this context, the application of metallic nanoparticles (NPs), especially gold (Au) and silver (Ag), has emerged as a promising strategy due to their remarkable antibacterial properties. This review examines research published between 2006 and 2023, focusing on leading journals in nanotechnology, materials science, and biomedical research. The primary applications explored are the efficacy of Ag and Au NPs as antibacterial agents, their synthesis methods, morphological properties, and mechanisms of action. An extensive review of the literature on NPs synthesis, morphology, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and effectiveness against various Gram(+/−) bacteria confirms the antibacterial efficacy of Au and Ag NPs. The synthesis methods and characteristics of NPs, such as size, shape, and surface charge, are crucial in determining their antibacterial activity, as these factors influence their interactions with bacterial cells. Furthermore, this review underscores the urgent necessity of standardizing synthesis techniques, MICs, and reporting protocols to enhance the comparability and reproducibility of future studies. Standardization is essential for ensuring the reliability of research findings and accelerating the clinical application of NP-based antimicrobial approaches. This review aims to propel NP-based antimicrobial strategies by elucidating the properties that enhance the antibacterial activity of Ag and Au NPs. By highlighting their inhibitory effects against various bacterial strains and relatively low cytotoxicity, this work positions Ag and Au NPs as promising materials for developing antibacterial agents, making a significant contribution to global efforts to combat antibiotic-resistant pathogens. [ABSTRACT FROM AUTHOR]

In this paper, a three-layer structure of silver particle (AgNP)-dielectric-metal is proposed and constructed based on the characteristics of AgNPs that can excite LSPR (Localized Surface Plasmon Resonance) in free space. In order to overcome the problem of AgNPs easily oxidizing in the air, this paper synthesizes AgNPs using the improved Tollens method and effectively suppresses the coffee-ring effect by changing the solution evaporation conditions, so that the distribution of AgNPs in the deposition area is relatively uniform. The structure proposed in this paper takes advantage of the flexibility of nanoparticle application. The AgNPs deposited on the dielectric layer can effectively localize energy and regulate the LSPR of the device well. The structure can not only achieve precise regulation of the LSPR resonance peak of AgNPs but also can be used as a SERS substrate. [ABSTRACT FROM AUTHOR]

Ag nanoparticles (NPs) were decorated on the surface of axial n-ZnO/p-CuO heterostructure (HS) nanowires (NWs) by using a catalytic-free and well-controlled technique called glancing angle deposition (GLAD). A typical high-resolution transmission electron microscope (HR-TEM) image shows formation of an Ag NPs on the surface of axial HS NW consisting of ZnO NW at the top and CuO NW at the bottom. Moreover, the photodetector (PD) based on Ag (NPs)-ZnO/CuO HS NW sample showed a high responsivity ( R λ ) of ~ 118 A/W, specific detectivity ( D ∗ ) of ∼ 1.38 × 10 12 Jones and noise equivalent power (NEP) as low as ∼ 2.42 × 10 - 12 W under 365 nm UV illumination. Further, the device showed a low dark current of ~ 5.25 nA at − 1 V applied bias with fast device response of ~ 0.072 s and ~ 1.73 s for rise and fall times respectively. Thus, the fabricated Ag (NPs)-ZnO/CuO HS NWs device can be a suitable applicant for UV photodetector application. [ABSTRACT FROM AUTHOR]

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Green synthesis of Ag nanoparticles (AgNPs) by using the plant extract is a very important strategy to gain efficient antimicrobial agents with strong antimicrobial activity and low toxicity. In this study, jujube seed extract (JSE) is utilized to green synthesis of AgNPs by both hydrothermal process and solution‐based approaches. UV–vis absorption spectroscopy and infrared spectroscopy (FTIR) spectra confirm that jujube seed extract functionalized Ag nanoparticles are formed by both approaches and jujube seed extract covered on the surface of Ag nanoparticles. Transmission electron microscopy (TEM) images indicate that the JSE‐AgNPs are spherical with the average diameter of 17.7 and 14.2 nm for the hydrothermal process and solution‐based approaches, respectively. X‐ray diffraction (XRD) results indicate that the JSE‐AgNPs prepared by both approaches have face‐centered cubic crystal structure. The antimicrobial activity test reveals that minimum inhibitory concentrations (MIC) of JSE‐AgNPs by the solution‐based method are 62.5, 125, and 62.5 µg mL−1 against Escherichia coli, Staphylococcus aureus, and Candida albicans, respectively. These results imply that the JSE‐AgNPs have potential to be developed as efficient antimicrobial agents. [ABSTRACT FROM AUTHOR]

A highly sensitive surface-enhanced Raman scattering (SERS) biosensor has been developed for the detection of microRNA-21 (miR-21) using an isothermal enzyme-free cascade amplification method involving catalytic hairpin assembly (CHA) and hybridization chain reaction (HCR). The CHA reaction is triggered by the target miR-21, which causes hairpin DNA (C1 and C2) to self-assemble into CHA products. After AgNPs@Capture captures the resulting CHA product, the HCR reaction is started, forming long-stranded DNA on the surface of AgNPs. A strong SERS signal is generated due to the presence of a large amount of the Raman reporter methylene blue (MB) in the vicinity of the SERS "hot spot" on the surface of AgNPs. The monitoring of the SERS signal changes of MB allows for the highly sensitive and specific detection of miR-21. In optimal conditions, the biosensor exhibits a satisfactory linear range and a low detection limit for miR-21 of 42.3 fM. Additionally, this SERS biosensor shows outstanding selectivity and reproducibility. The application of this methodology to clinical blood samples allows for the differentiation of cancer patients from healthy controls. As a result, the CHA-HCR amplification strategy used in this SERS biosensor could be a useful tool for miRNA detection and early cancer screening. [ABSTRACT FROM AUTHOR]

Monitoring of plant hormone ethylene plays a crucial role in managing the growth and development of plants, especially in the ripening of fruits and the opening of flowers. Here, a highly sensitive ethylene sensor is demonstrated using silver nanoparticle (Ag NP)-decorated zinc oxide nanoflowers (ZnO NFs), prepared through a facile and low-temperature chemical synthesis. The results indicate that Ag NP decoration on the surface of ZnO NFs improved the ethylene sensing properties under ultraviolet (UV) illumination. With an optimized UV light intensity of 5 mW/cm², the sensing response to 40 ppm of ethylene gas increased from 13.27% to 52.83%. The sensors exhibit a strong linear response to ethylene gas within the range of 10-70 ppm, with a low detection limit of 5 ppm. Moreover, the Ag-decorated ZnO NFs sensors demonstrated good repeatability, excellent long-term stability, and high selectivity toward ethylene gas. The sensing mechanism is attributed to the catalytic effectiveness and localized surface plasmon resonance of Ag NPs. These results suggest that UV-induced Ag-decorated ZnO NFs are promising for practical application in fruit ripening monitoring for supply chain management. [ABSTRACT FROM AUTHOR]

The rapid increase of carbon dioxide (CO2) in the atmosphere has sparked a global enthusiasm for carbon recycling. Photocatalytic CO2 reduction with water into carbon–containing products has attracted much attention since it can convert solar energy to the chemical potential of the products and CO2 to valuable compounds at the same time. One of the main products in the photocatalytic reaction system is carbon monoxide (CO), a useful compound for the one‐carbon chemistry and related ones. The current shortage of this system is the low production efficiency, demanding us to improve the activity of the photocatalyst. In this perspective article, by taking a calcium titanate (CaTiO3, CTO) photocatalyst with silver cocatalyst (Ag/CTO) and so on as examples that can promote the selective photocatalytic CO2 reduction with water, we shortly review some strategies to improve the photocatalytic activity such as fabrication of well–structured crystal photocatalysts, development of the surface property and cocatalyst, improvement of surface CO2 adsorption, and improvement of photoabsorption. These concepts will be widely applied and contribute to further development of photocatalytic systems. [ABSTRACT FROM AUTHOR]

Hafnia sp. was one of the specific spoilage bacteria in aquatic products, and the aim of the study was to investigate the inhibition ability of the silver nanoparticles (AgNPs) biosynthesis by an aqueous extract of Prunus persica leaves toward the spoilage-related virulence factors of Hafnia sp. The synthesized P-AgNPs were spherical, with a mean particle size of 36.3 nm and zeta potential of 21.8 ± 1.33 mV. In addition, the inhibition effects of P-AgNPs on the growth of two Hafnia sp. strains and their quorum sensing regulated virulence factors, such as the formation of biofilm, secretion of N -acetyl-homoserine lactone (AHLs), proteases, and exopolysaccharides, as well as their swarming and swimming motilities were evaluated. P-AgNPs had a minimum inhibitory concentration (MIC) of 64 μg ml−1 against the two Hafnia sp. strains. When the concentration of P-AgNPs was below MIC, it could inhibit the formation of biofilms by Hafnia sp at 8–32 μg ml−1, but it promoted the formation of biofilms by Hafnia sp at 0.5–4 μg ml−1. P-AgNPs exhibited diverse inhibiting effects on AHLs and protease production, swimming, and swarming motilities at various concentrations. [ABSTRACT FROM AUTHOR]

Methylene blue dye, being toxic, carcinogenic and non-biodegradable, poses a serious threat for human health and environmental safety. The effective and time-saving removal of such industrial dye necessitates the use of innovative technologies such as silver nanoparticle-based catalysis. Utilizing a pulsed Nd:YAG laser operating at the second harmonic generation of 532 nm with 2.6 J energy per pulse and 10 ns pulse duration, Ag nanoparticles were synthesized via an eco-friendly method with sodium dodecyl sulphate (SDS) as a capping agent. Different exposure times (15, 30, and 45 min) resulted in varying nanoparticle sizes. Characterization was achieved through UV–Vis absorption spectroscopy, scanning electron microscopy (SEM) imaging, and energy dispersive X-ray (EDX). Lorentzian fitting was used to model nanoparticle size, aligning well with SEM results. Mie's theory was applied to evaluate the absorption, scattering, and extinction cross-sectional area spectra. EDX revealed increasing Ag and carbon content with exposure time. The SDS-caped AgNPs nanoparticles were tested as catalyst for methylene blue degradation, achieving up to 92.5% removal in just 12 min with a rate constant of 0.2626 min−1, suggesting efficient and time-saving catalyst compared to previously reported Ag-based nanocatalysts. [ABSTRACT FROM AUTHOR]

The dehydrocoupling reaction between alcohols and hydrosilanes is considered to be one of the most atom-economical ways to produce Si–O coupling compounds because its byproduct is only hydrogen (H2), which make it extremely environmentally friendly. In past decades, various kinds of homogeneous catalysts for the dehydrocoupling of alcohols and hydrosilanes, such as transition metal complexes, alkaline earth metals, alkali metals, and noble metal complexes, have been reported for their good activity and selectivity. Nevertheless, the practical applications of these catalysts still remain unsatisfactory, which is mainly restricted by environmental impact and non-reusability. A facile and recyclable heterogeneous catalyst, ultra-small Ag nanoparticles supported on porous carbon (Ag/C) for the etherification of silanes, has been developed. It has high catalytic activity for the Si–O coupling reaction, and the apparent activation energy of the reaction is about 30 kJ/mol. The ultra-small Ag nanoparticles dispersed in the catalyst through the carrier C have an enrichment effect on all reactants, which makes the reactants reach the adsorption saturation state on the surface of Ag nanoparticles, thus accelerating the coupling reaction process and verifying that the kinetics of the reaction of the catalyst indicate a zero-grade reaction. [ABSTRACT FROM AUTHOR]

Surface‐enhanced Raman scattering (SERS) is an ultrasensitive spectroscopic analysis technique widely used for molecule detection. However, manufacturing uniform, stable, and ultrasensitive substrates remains a challenge for the practical application of the SERS technology. Precious metals and semiconductors have been proved to be attractive and universal for SERS detection. In this work, a facile strategy is applied to prepare uniform three‐dimensional (3D) Ag@TiO2 nanostructures as SERS sensors. The Scanning electron microscopy and X‐ray photoelectron spectroscopy results indicate that silver nanoparticles are uniformly deposited into the pores of the TiO2 nanocavity arrays. The 3D hybrid substrate presents highly sensitive SERS signals of 4‐mercaptobenzoicacid (4‐MBA) with a detection limitation as low as 10−17 M. To prevent the oxidization of Ag and keep the activity of the film, a polymer mask was deposited on the SERS substrate and brought about excellent stability after weeks of reserving in air. In a nutshell, a SERS substrate with a high sensitivity and stability as well as good uniformity has been successfully developed in this work, which has a potential application for high‐precision SERS detection. [ABSTRACT FROM AUTHOR]

The synergy of adsorption and photocatalysis is a good method to remove organic pollutants in wastewater. In recent decades, persistent photocatalysis has gained considerable interest for its ability to sustain the catalytic degradation of organic pollutants in the dark. Herein, we report three different TiO2 nanomaterials to remove tetracycline hydrochloride (TCH) in solution. We found that the removal ability of TiO2, Ni-TiO2, and Ag/Ni-TiO2 is 8.8 mg/g, 13.9 mg/g and 23.4 mg/g, respectively, when the initial concentration of TCH is 50 mg/L. Chemical adsorption could be the rate-determining step in the TCH adsorption process. Moreover, Ag nanoparticles dispersed on Ni doped TiO2 surface act as traps to capture photo-generated electrons upon illumination with indoor light. The holes in Ag/Ni-TiO2 serve as critical oxidative species in TCH degradation under dark conditions. This work provides new insights into the design of persistent photocatalysts that can be activated by weak illumination and degrade organic pollutants in wastewater after sunset. [ABSTRACT FROM AUTHOR]

The accurate and sensitive determination of tyrosine is of paramount value. In this work, we reported the synthesis and characterization of a new nanohybrid composed of silver nanoparticles and hollow carbon nanospheres (Ag/HMCS) for the amperometric sensing of tyrosine. The Ag/HMCS nanohybrid was used to modify electrodes and to fabricate an amperometric sensor for tyrosine at a working potential of 450 mV in aqueous 0.1 M phosphate buffer at pH 7.0. Under optimal conditions, the sensor determined tyrosine from 0.08 to 100 μM with a detection limit of 0.02 μM. [ABSTRACT FROM AUTHOR]

Ag@SiO2 core–shell nanoparticles (NPs) have attracted extensive attention for their excellent surface-enhanced Raman scattering (SERS)-fluorescence (SEF) and their potential applications in sensing, biomedicine, and imaging. The thickness of silica shell plays a crucial role in determining the SERS-SEF properties. However, a few studies have been made to synthesize Ag@SiO2 core–shell NPs with controllable thickness of silica shell and systematic research about the optimized SERS-SEF enhancement. Here, Ag@SiO2 core–shell NPs were prepared by a modified one-pot synthetic method via reducing AgNO3 using formaldehyde in the presence of cetyltrimethylammonium chloride and sequentially hydrolyzing tetraethyl orthosilicate (TEOS). The effects of the type of surfactant and the concentrations of NaOH and AgNO3 on the size and morphology of the resulting Ag@SiO2 core–shell NPs were systematically investigated. The thickness of the silica shell could be finely tuned from 9.3 to 38.9 nm by easily adjusting the amount of TEOS. The crystal violet molecule was used for examining SERS and SEF properties of Ag@SiO2 core–shell NPs with different SiO2 thicknesses. The current work will provide guidance for further understanding the growth mechanism of Ag@SiO2 core–shell NPs and how the thickness of silica shell affects the SERS-SEF properties. [ABSTRACT FROM AUTHOR]

The main goal of this research is to investigate the effectiveness of graphitic carbon nitride (g-C3N4, g-CN) in both bulk and nanosheet forms, which have been surface-modified with silver nanoparticles (Ag NPs), as photocatalysts for the degradation of acid orange 7 (AO7), a model dye. The photodegradation of AO7 dye molecules in water was used to test the potential photocatalytic properties of these powder materials under two different lamps with wavelengths of 368 nm (UV light) and 420 nm (VIS light). To produce Ag NPs (Ag content 0.5, 1.5, and 3 wt%) on the g-CN materials, a new synthesis route based on a wet and low-temperature method was proposed, eliminating the need for reducing agents. The photodegradation activity of the samples increased with increasing silver content, with the best photocatalytic performances achieved for bulk g-CN samples and nanosheet silver-modified samples (with the highest content of 3 wt% Ag) under UV light, i.e., more than 75% and 78%, respectively. The VIS-induced photocatalytic activity of both examined series was higher than that of UV. The highest activities of 92% and 98% were achieved for the 1.5% Ag-modified g-CN bulk and nanosheet materials. This research presents an innovative, affordable, and environmentally friendly chemical approach to synthesizing photocatalysts that can be used for degrading organic pollutants in wastewater treatment. [ABSTRACT FROM AUTHOR]

A novel Cr-doped BaTiO3 aerogel was successfully synthesized using a co-gelation technique that involves two metallic alkoxides and a supercritical drying method. This freshly prepared aerogel has a high specific surface area of over 100 m2/g and exhibits improved responsiveness to the simulated sunlight spectrum. Methyl orange (MO) was chosen as the simulated pollutant, and the results reveal that the Cr-doped BaTiO3 aerogel, when modified with the noble metal silver (Ag), achieves a pollutant removal rate approximately 3.2 times higher than that of the commercially available P25, reaching up to 92% within 60 min. The excellent photocatalytic performance of the Ag-modified Cr-doped BaTiO3 aerogel can be primarily attributed to its extensive specific surface area and three-dimensional porous architecture. Furthermore, the incorporation of Ag nanoparticles effectively suppresses the recombination of photo-generated electrons and holes. Stability and reusability tests have confirmed the reliability of the Ag-modified Cr-doped BaTiO3 aerogel. Therefore, this material emerges as a highly promising candidate for the treatment of textile wastewater. [ABSTRACT FROM AUTHOR]

Conductive paste inks have received considerable attention as facile conductive materials for the formation of electrode layers. However, conventional paste inks result in films with poor surface morphology. In addition, they require a high thermal annealing temperature for achieving high electrical conductivity because of their organic/inorganic composite structure, in which nanosized metal particles and polymeric organic binders are mixed in solvents. In this work, we prepare solvent-free and polymeric-binder-free metal nanoparticle (NP) fluids, which can be used as facile conductive pastes for forming an electrode layer after sintering at a considerably low temperature. We employ thiol-terminated imidazolium-type ionic liquid (IL-SH) molecules with a small molecular weight and fluidic behavior as the surface ligands of Ag NPs. IL-SH-stabilized Ag NPs exhibit fluidic behavior and metallic conducting properties at a considerably low sintering temperature of 250 °C. [ABSTRACT FROM AUTHOR]

Medical protective masks with both high antibacterial activity and filtration efficiency have gained wide interest due to sporadic respiratory disease outbreaks. Previous studies have focused on improving a single function (antibacterial activity or filtration) of the mask performance. Herein, we developed silver nanoparticles-decorated PVDF membranes (AgNPs/PVDF) with both high antibacterial activity and filtration efficiency. Our results show that AgNPs/PVDF membranes have antibacterial efficiency of 99.98% and 99.86% against E. coli and S. aureus , respectively. The bacterial filtration efficiency is higher than 95%. PM0.26 filtration efficiency can be maintained above 95% after continuous filtration for 144 min. Adding AgNPs also promotes distinct hierarchical structure formation, which could improveme the filtration efficiency. This study provides a new methodology to fabricate antibacterial membranes doped with metal nanoparticles with promising applications in personal protective equipment development. [ABSTRACT FROM AUTHOR]

This paper reports on the biosynthesis, characterization, as well as the bactericide and cytotoxic properties of silver nanoparticles supported on bovine bone powder (Ag-NPs/BBP). The silver nanoparticles were obtained through the bioreduction of AgNO3, using an infusion of Heterotheca inuloides leaves and flowers as a reducing agent and bovine bone powder as a support. The ratio of Ag-NPs/bovine bone powder was set as 1:10. The characterization was performed with SEM–EDS, XRD, UV–Vis, and TEM, which showed the formation of nanoparticles with an average size of 22.6 ± 10.8 nm and a quasi-spherical Ag-NPs morphology supported on the BBP surface. The nanocomposite exhibited a band gap of 2.19 eV. The minimal inhibitory concentration and the minimal bactericidal concentration against S. aureus, E. coli, and S. epidermidis were determined for each strain. In addition, the cytotoxic evaluation of the Ag-NPs/BBP on J774.2 mouse macrophage cells was performed. The Ag-NPs/BBP exhibited a bactericide effect on the strains studied, and the cytotoxicity had a dose-dependent behavior on the cells studied. Therefore, it was found that the ecofriendly synthesized Ag-NPs supported on bovine bone powder resulted in an effective bactericidal system against the strains studied, without significant cytotoxicity. [ABSTRACT FROM AUTHOR]

In this study, the celestine (natural strontium sulfate) is first converted to strontium carbonate (SrCO3). Then, magnetic strontium ferrite nanocomposite was produced from the reaction of obtained SrCO3 (in HNO3) and Fe(NO3)3 solution. Biosynthesized Ag nanoparticles (NPs) supported on SrFe2O4 were prepared by the aqueous horehound (Marrubium vulgare L.) leaf extract. The synthesized nanocomposites were analyzed using different characterization techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), field emission scanning electron microscope (FESEM), and X-ray spectroscopy (EDX). The FESEM analysis of Ag/SrFe2O4 nanocomposite confirms the formation of spherical Ag NPs dispersed on the surface of strontium ferrite with an average particle size below 50 nm. The reduction/decolorization time of 10 ppm methyl orange (MO) solution in the presence of 10.6 × 10−3 M sodium borohydride (NaBH4) solution and 9 mg of Ag/SrFe2O4 catalyst with good activity and reusability was 2.5 min. [ABSTRACT FROM AUTHOR]

The use of nanofiber patches has received considerable attention as a promising solution for overcoming challenges in drug delivery. In this study, silver nanoparticles (Ag NPs) were incorporated in chitosan (CS), hyaluronic acid (HYA), and polyvinyl alcohol (PVA) to form nanofibers (namely, the CS/HYA/PVA-Ag nanofiber) for the controllable release of curcumin (CUR). The CUR release from the CS/HYA/PVA-Ag nanofibers consistently happened sustainably. Therefore, the prepared CS/HYA/PVA-Ag nanofibers show great promise in terms of their ability to expand the field of pH-dependent transdermal drug delivery (TDD) and sustainably release drugs. Additionally, the scratch assay results of these nanofibers further support their potential applications in wound healing. [ABSTRACT FROM AUTHOR]

The syntheses of Ag-based nanoparticles (NPs) with the assistance of plant extracts have been shown to be environmentally benign and cost-effective alternatives to conventional chemical syntheses. This study discusses the application of Paliurus spina-christi, Juglans regia, Humulus lupulus, and Sambucus nigra leaf extracts for in situ synthesis of Ag-based NPs on cotton fabric modified with citric acid. The presence of NPs with an average size ranging from 57 to 99 nm on the fiber surface was confirmed by FESEM. XPS analysis indicated that metallic (Ag0) and/or ionic silver (Ag2O and AgO) appeared on the surface of the modified cotton. The chemical composition, size, shape, and amounts of synthesized NPs were strongly dependent on the applied plant extract. All fabricated nanocomposites exhibited excellent antifungal activity against yeast Candida albicans. Antibacterial activity was significantly stronger against Gram-positive bacteria Staphylococcus aureus than Gram-negative bacteria Escherichia coli. In addition, 99% of silver was retained on the samples after 24 h of contact with physiological saline solution, implying a high stability of nanoparticles. Cytotoxic activity towards HaCaT and MRC5 cells was only observed for the sample synthetized in the presence of H. lupulus extract. Excellent antimicrobial activity and non-cytotoxicity make the developed composites efficient candidates for medicinal applications. [ABSTRACT FROM AUTHOR]

Noble metal/semiconductor nanocomposites have been synthesized using various methods, including precipitation and hydrothermal and electrochemical processes. Among these, the photodeposition method stands out for its simplicity, without the need for high temperatures, redox agents, or complex steps. This method facilitates the control over noble metal nanoparticle size by adjusting parameters such as metal precursor concentration, irradiation time, and power. However, understanding the interaction between solid and liquid interfaces, particularly the role of solution viscosity in the growth process, remains a challenge. This knowledge is crucial for precise control over nanoparticle size and distribution. Our study highlights the influence of viscosity, manipulated through different alcohols, on the formation of Ag nanostructures on TiO2 thin films via photodeposition, offering insights into optimizing nanocomposite synthesis. [ABSTRACT FROM AUTHOR]

To avoid harm to humans and devices, developing electromagnetic interference (EMI) shielding materials possessing high shielding efficiency and enhanced electromagnetic (EM) wave absorption properties is of fundamental importance. Preventing threats caused by EMI and reducing the secondary pollution of EM waves are critical requirements for materials. In the research described here, composites of Ag nanoparticles coated with poly p-phenylene terephthalamide (PPTA) nonwoven and Fe3O4 decorated MXene nanosheets were prepared by electroless silver plating and Fe3O4-MXene deposition. The top and bottom layers of the composites were Fe3O4 nanoparticle-decorated MXene nanosheets and silicone rubber, while the middle layer consisted of a Ag nanoparticle-coated PPTA nonwoven fabric. The formation of the sandwich structure, the electromagnetic compounding, and the porous structure of the PPTA nonwoven fabric coated with Ag nanoparticles endowed the composites with excellent EMI shielding properties. An EMI shielding effectiveness of 89.92 dB was achieved in the frequency range of 8.2–12.4 GHz. The absorption coefficient A of the composites reached 0.203, which was noticeably enhanced compared with 0.013 of Ag nanoparticle-coated PPTA nonwoven fabric. [ABSTRACT FROM AUTHOR]

Ag nanoparticles were developed using plant extracts from the various plant species, including the flowers, leaves, and peels. UV–visible spectroscopy with a wavelength range of 400–450 nm was used to confirm the surface Plasmon resonance absorption and Ag0 reduction of the synthesized Ag nanoparticles. Using the XRD technique, the cubic structure of Ag nanoparticles and their refined crystallinity were examined. According to SEM and TEM analysis, leaf and peel extracts produced spherical and semi-spherical Ag nanoparticles, while flower extract biomolecules produced rod-like Ag nanoparticles. FTIR and EDX spectroscopy were used to confirm the presence of plant extract bio-compounds, Ag metal reduction, and interaction with response materials. For flower extract 94%, 82% for leaf extract, and 79% for peel extract, photocatalytic degradation of MB dye was achieved, respectively. With rates of 0.01478 min−1 for flower extract, 0.013245 min−1 for leaf extract, and 0.012895 min−1 for peel extract, the degradation rate followed a pseudo-first-order kinetics. Ag nanoparticles' antimicrobial effectiveness against S. aureus, E. coli, P. aeruginosa, and C. albicans has also been proven. S. aureus and C. albicans showed the highest antimicrobial sensitivity to green-synthesized Ag nanoparticles. As a result, this study suggests that compared to other nano-phase materials, Ag nanoparticles produced through green synthesis method and pronounced the noxious free and improved activities in biological as well as wastewater treatment. [ABSTRACT FROM AUTHOR]

Quorum sensing (QS) is a communication pattern between bacteria, hence the inhibition of bacterial QS system could be used as a new strategy to the control the spoilage caused by bacteria, and to some extent could avoid the bacteria drug resistance. In the study, dandelion water extract mediated biosynthesis Ag nanoparticles (D-AgNPs) was prepared with AgN03 as silver source and dandelion water extract as reducing agent. Its structure was characterized by ultraviolet visible absorption spectroscopy (UV-vis), dynamic light scattering (DLS), Zeta potential, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray energy spectrum (EDS). It was found that the synthesized D-AgNPs were spherical, with an average particle size of 13.9 nm and Zeta potential of (-14.07±0.25) mV. The effects of D-AgNPs on the growth of two Hafnia strains and quorum sensing regulated virulence factors such as biofilm, AHLs, proteases, exopolysaccharides, swimming and swarming motilities were determined. It was found that the minimum inhibitory concentration of D-AgNPs against Hafnia was 128 |g/mL, and could inhibit the formation of the biofilms of Hafnia at 1/16-1/2 MIC (8-64 |g/mL), whereas promoted its biofilm formation at 1/128-1/32 MIC (1-4 µg/mL). D-AgNPs showed different inhibition abilities on the AHLs and protease production, as well as swimming and swarming motilities; however, sub-MIC D-AgNPs promoted the production of exopolysaccharides. It is proved that D-AgNPs could be used as quorum sensing inhibitor. [ABSTRACT FROM AUTHOR]

The coupling between the incident light and the highly reflective nanoparticles is believed to potentially raise the reflective intensity of PSCLCs by creating a channel that causes the incident light to reach the helical CLCs and reflect outward. Therefore, in this research Ag nanoparticles were blended into polymer stabilized cholesteric liquid crystals (PSCLCs) to enhance their reflective intensity. A small amount of blending Ag nanoparticles (less than 1.0 wt%) in PSCLCs that investigated with 1wt% ‐ 3wt% RM 257 polymerization effectively leads to an increase of the reflective intensity of up to 17%, but has little effect on their thermally induced dynamical reflection variations. These results indicate that the blending of Ag nanoparticles in PSCLCs is an adequate method for the investigation of highly reflective PSCLCs. [ABSTRACT FROM AUTHOR]

Solar-driven photocatalytic CO2 conversion is a promising strategy to alleviate the energy crisis and reduce the level of CO2 emissions. In this study, GaN@β-Ga2O3 core–shell nanowire (NW) arrays were prepared via the thermal oxidation of GaN NWs, and their photocatalytic CO2 reduction performance was investigated. GaN@β-Ga2O3 NWs exhibited superior photocatalytic activity compared to GaN NWs and β-Ga2O3 NWs under simulated sunlight irradiation. The average CO production rate reached ∼447.30 μmol g–1 h–1 within 3 h. The photocatalytic reduction process was further enhanced using GaN@β-Ga2O3 NWs with Ag nanoparticles of ∼18 nm size as cocatalysts, and its average rate increased to ∼689.18 μmol g–1 h–1. The ternary heterostructured photocatalyst demonstrated excellent synergistic effects and high efficiency in environmental protection and energy conversion applications. [ABSTRACT FROM AUTHOR]