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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]

Noble metal nanoparticles (NMNPs) are crucial for catalytic processes, but their recycling and aggregation present challenges. Immobilizing NMNPs on substrates often reduces their catalytic activity due to hindered diffusion and decreased surface area. This study presents a novel approach using silver (N-Isopropylacrylamide Co methyl acrylic acid) (Ag@PNM) nanoparticles, characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic light scattering transmission (DLS), transmission electron microscopy (TEM) and UV–visible spectroscopy. A catalytic membrane with silver nanoparticles (Ag NPs) embedded in a three-dimensional (3D) network of hybrid microgels was fabricated. The microgels are filtered into a microporous membrane and expanded to secure the Ag NPs, enhancing catalytic efficiency for 4-nitrophenol reduction through improved mass transfer and exposure of the nanoparticles. The membrane shows high stability and performance, with a turnover frequency of 77.5 h−1 and an apparent rate constant (kapp) of 0.15 s−1. Additionally, the PES/Ag@PNM membrane demonstrated effective reduction of 4-nitrophenol. The straightforward synthesis and stability of this approach make it a promising and cost-effective solution for industrial applications. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) has practical applications in healthcare, food security, and environmental protection. The current study has been focused on creating H2O2 sensors using a bimetallic composition of polypyrrole/Cobalt-silver on indium tin oxide (ITO) through electrochemical fabrication. Composite hybrid materials comprising Co@Ag/PPy/ITO were successfully synthesized using chronoamperometry and pulsed electrodeposition techniques. The obtained electrode (Co@Ag/PPy/ITO) was studied using scanning electron microscopy (SEM), ultraviolet–visible, and cyclic voltammetry techniques. The energy-dispersive X-ray spectroscopy and SEM revealed that silver and cobalt nanoparticles were distributed on the PPy surface, forming fern-like structures. A detailed investigation of the electrochemical properties of the bimetallic composition was conducted using cyclic voltammetry (CV), chronoamperometry, and electrochemical impedance spectroscopy. The amperometric method and CV were used to carry out the electrochemical detection of H2O2. The non-enzymatic H2O2 sensor exhibited an enhanced amperometry response, showing a higher sensitivity of 3.664 mA mM−1 cm−2 within a linear range spanning 0.12–2.36 mM. Notably, the sensor achieved a low detection limit of 1.985 μM (S/N = 3). Additionally, the nanocomposite hybrids demonstrated superior stability, repeatability, and reproducibility, making this sensor suitable for long-term use. [ABSTRACT FROM AUTHOR]

The Ag-PSi@SiC@C electrode features a substantially higher lithium-ion mobility of 2.4 × 10−9 cm2·s−1, which is significantly greater than the mobility of silicon at 5.1 × 10−12 cm2·s−1. With this anode, the half-cell exhibits excellent rate capability and cycling stability at a current density of 2.0 A/g, with a capacity of 1321.7 mAh/g that is maintained over 200 cycles, dropping only to 962.6 mAh/g. [Display omitted] Silicon-based material is regarded as one of the most promising anodes for next-generation high-performance lithium-ion batteries (LIBs) due to its high theoretical capacity and low cost. Harnessing silicon carbide's robustness, we designed a novel porous silicon with a sandwich structure of carbon/silicon carbide/Ag-modified porous silicon (Ag-PSi@SiC@C). Different from the conventional Si C interface characterized by a frail connection, a robust dual covalent bond configuration, dependent on Si C and Si O C, has been successfully established. Moreover, the innovative sandwich structure effectively reduces detrimental side reactions on the surface, eases volume expansion, and bolsters the structural integrity of the silicon anode. The incorporation of silver nanoparticles contributes to an improvement in overall electron transport capacity and enhances the kinetics of the overall reaction. Consequently, the Ag-PSi@SiC@C electrode, benefiting from the aforementioned advantages, demonstrates a notably elevated lithium-ion mobility (2.4 * 10−9 cm2·s−1), surpassing that of silicon (5.1 * 10−12 cm2·s−1). The half-cell featuring Ag-PSi@SiC@C as the anode demonstrated robust rate cycling stability at 2.0 A/g, maintaining a capacity of 1321.7 mAh/g, and after 200 cycles, it retained 962.6 mAh/g. Additionally, the full-cell, featuring an Ag-PSi@SiC@C anode and a LiFePO 4 (LFP) cathode, exhibits outstanding longevity. Hence, the proposed approach has the potential to unearth novel avenues for the extended exploration of high-performance silicon-carbon anodes for LIBs. [ABSTRACT FROM AUTHOR]

Localized surface plasmon resonances in plasmonic nanoparticles enable effective photon harvesting and generate energetic electrons and holes. However, fast charge recombination and surface contamination due to reactant-involved synthesis can significantly hinder the activity. Herein, we report a facile, solution-processed synthesis of hybrid uncoated silver nanoparticles combined with silicon nanocrystals to address these issues. The resulting hybrid nanocolloid exhibits enhanced photocatalytic CO2 reduction, achieving 1552 μmol g−1 and 100% selectivity for CO production. [ABSTRACT FROM AUTHOR]

The development of an environmentally benign method for the synthesis of nanoparticles has been facilitated by green chemistry. "Green synthesis" uses a range of biological elements like microbes, plants, and other biodegradable materials to produce NPs. Active biomolecules that are secreted by natural strains and present in the plant extracts serve as both reducing and capping/stabilizing agents. Microorganisms' intracellular enzymes can reduce metal ions, which explains how NPs might potentially nucleate. Plant-based synthesis of nanomaterials is particularly promising owing to abundant resources, simplicity of synthesis, and low cost. Silver nanoparticles (AgNPs) are attracting great attention in the research community due to their wide variety of applications in chemistry, food technology, microbiology, and biomedicine. Recent years have seen a large amount of research on the bio-genic synthesis of AgNPs employing biomaterials like plant extract and bacteria as reducing agents. Herein we discuss a thorough overview of the plant-based synthesis of silver nanoparticles (AgNPs), characterization approaches, applications, and toxicity. The review covers the green chemistry and nanotechnology elements of producing AgNPs, including a thorough discussion of the plant extract mediated synthesis, detailed formation mechanism, and a well-balanced emphasis on hazards and advantages. Based on current developments, the optimisation strategies, applications, and interdisciplinary characteristics are also covered in detail. • Plant-based synthesis of nanomaterials is particularly promising. • A comprehensive review on plant-based AgNPs synthesis. • Synthesis, characterization approaches, applications and toxicity are discussed. [ABSTRACT FROM AUTHOR]

The AgNPs‐Rsvl complex was investigated for its anti‐cancer effects on human breast cancer cell lines. The UV–vis spectrophotometer was used to perform synthesized AgNPs‐Rsvl binding analyses. The size and morphology of the AgNPs were determined by field emission gun‐transmission electron microscopy (FEG‐TEM). The surface chemical signatures of AgNPs nanocomposites were assessed using FT‐IR spectroscopy, and the zeta potential (ζ potential) of various AgNPs colloids was measured using the Zetasizer Nano ZS analyzer. Cell proliferation was analyzed using the XTT method and cell apoptosis was analyzed using the AnnexinV‐fluorescein isothiocyanate (FITC)/PI method. The effects of resveratrol were evaluated on human breast cancer cell lines (MDA‐MB‐231 and MCF‐7). As a result of flow cytometry, a decrease in viability was observed in the MDA‐MB‐231 cells, and an increase in early apoptotic, late apoptotic, and necrotic values was observed. Resveratrol arrests the cell cycle in the G0/G1 phase but when used with AgNPs, the cell cycle arrests at the S phase. The combination of resveratrol and AgNPs exhibited a cytotoxic effect on cancer cells, with MDA‐MB‐231 breast cancer cells being the most sensitive to AgNPs‐Rsvl. Resveratrol and AgNPs arrested the cell cycle and increased apoptosis, indicating their potential use in breast cancer treatment. [ABSTRACT FROM AUTHOR]

Silver nanoparticles modified copper oxide nanocomposite thin films (Ag‐CuO NC TFs) and pristine CuO TF were successfully synthesized on copper substrates using a chemical oxidation route. X‐ray diffractometry (XRD) characterization of Ag‐CuO NC TFs revealed the formation of monoclinic crystal structured CuO. Scanning electron microscopy (SEM) images showed a star‐like grain morphology of the Ag‐CuO NC TFs. Energy dispersive X‐ray spectroscopy (EDX) analysis ascertained the presence of anticipated elements without impurities. Fourier transform infrared spectroscopy (FTIR) investigation confirmed the presence of Ag NPs on CuO in the Ag‐CuO NC TFs. Raman spectroscopy examination indicated the presence of a spinel structure with vibrational and tetrahedral sites. UV‐Vis‐NIR reflectance analysis demonstrated that Ag‐CuO NC TFs with 2.0 wt.% Ag NPs exhibited solar absorptance of 72.39 %, thermal emittance of 4.3 %, and a highest solar selectivity of 16.83 among the prepared thin films. These results suggest that the Ag‐CuO NC TFs could be promising candidates for use as solar selective absorbers in solar thermal energy conversion devices. [ABSTRACT FROM AUTHOR]

Complex mixtures that may contain hundreds, if not thousands, of unique compounds pose an analytical challenge for complete and detailed analyses. For example, green tea is a well-known complex substance requiring advanced separation techniques and ultrasensitive detection methods for full characterization. Separation and identification of components in green tea help gauge tea quality, as green tea is one of the most consumed beverages in the world. In this work, the coupling of two-dimensional liquid chromatography (2D-LC) and electrochemical surface-enhanced Raman spectroscopy (EC-SERS) was explored for the first time to analyze compounds in green tea. 2D-LC offers enhanced separation compared to conventional HPLC systems due to the second dimension of separation. EC-SERS was used as an offline detection modality and qualitative tool to help identify the compounds in green tea fractions collected from the second dimension separation. 2D-LC and EC-SERS are coupled in this work for the first time and offer a pathway forward for sensitive and selective separation and identification of components in complex mixtures. [ABSTRACT FROM AUTHOR]

• Presenting a facile method using pink flower petals as a new source of green synthesis of silver nanoparticles. • SEM analysis showed that the biosynthesized nanoparticles with pink rose petals had a spherical shape and an average size of 26 nm. • Biosynthesized nanoparticles have Ag0 structure. • Biosynthesized silver nanoparticles with a new synthesis source have antibacterial effects, the lowest minimum inhibitory concentration (MIC) of silver nanoparticles is 400 μg/ml against multidrug-resistant Staphylococcus aureus and MIC on multidrug-resistant Escherichia coli, Acinetobacter baumannii , and resistant Acinetobacter. It was 800 µg/ml, 3200 µg/ml and 1600 µg/ml, respectively, to several drugs and Klebsiella pneumoniae. Drug resistant bacterial infections can be fatal for disabled people needing multiple medications and new effective antibacterial drugs such as biosynthesized nanoparticles are needed. A cost-effective and green method was studied for the biosynthesis of silver nanoparticles using pink rose petals. Silver nanoparticles (AgNP) were synthesized using the petals of pink rose flowers. The AgNPs were characterized using FITR, SEM, XRD, and EDS analyses. The antibacterial activity of the AgNPs against multidrug-resistant bacterial pathogens Staphylococcus aureus, Escherichia coli, Acinetobacter baumannii , and colistin-resistant Klebsiella pneumoniae were studied using the microplate method. Th AgNPs had a spherical shape and an average size of 26 nm. XRD analysis showed that the nanoparticles were Ag0. Antibacterial activity was the highest against the multidrug-resistant S. aureus the minimum inhibitory concentration (MIC) being 400 µg/ml AgNPs. The multidrug-resistant E. coli , multidrug-resistant A. baumannii , and colistin-resistant K. pneumoniae MICs were 800 µg/ml, 3200 µg/ml, and 1600 µg/ml, respectively. The green synthesized of AgNPS using pink rose petals and their antibacterial effects offer material for the treatments of common multidrug-resistant bacterial pathogens. [ABSTRACT FROM AUTHOR]

In this study, a highly sensitive electrochemical sensor for the detection of bisphenol A (BPA) was developed by modifying a screen-printed carbon electrode (SPCE) with silver nanoparticles (AgNPs) and graphene oxide (GO) composites. The electrochemical properties of the modified electrode interface were meticulously investigated through cyclic voltammetry (CV) and electrochemical impedance spectroscopy, employing 1.0 mM [Fe(CN)6]3–/[Fe(CN)6]4– as a redox probe. The findings demonstrate that the AgNPs/GO/SPCE composite exhibits superior electrical conductivity and facilitates rapid electron transfer compared to both GO/SPCE and SPCE alone. The electrochemical behavior of BPA on the AgNPs/GO/SPCE electrode was comprehensively studied using CV, revealing exceptional electrocatalytic properties for BPA oxidation. To assess the analytical performance, differential pulse voltammetry was employed. Results unequivocally show a significant improvement in the electrochemical responses when using AgNPs/GO/SPCE. Calibration curves exhibited linear ranges of 0.25–2.19 μM with a remarkable limit of detection of 0.046 μM for BPA. Furthermore, the established method was applied for the determination of BPA in plastic products, achieving satisfactory reproducibility and recovery. This novel AgNPs/GO/SPCE-based sensor holds promise for the sensitive and reliable detection of BPA in various environmental and industrial applications. [ABSTRACT FROM AUTHOR]

In this study, the extract obtained from the flowers of the Anchusa azurea (AA) plant was mixed with silver nitrate to obtain silver nanoparticles. The ion sensing ability of the obtained bio-sourced silver nanoparticles in aqueous solutions was investigated and the presence of Hg2+ ions was determined colorimetrically. Silver nanoparticles (AgNPs) prepared on Green Chemistry method, which is both an environmentally friendly and cost-effective synthesis technique, were characterised using different analytical tools. The mean particle size of AA-AgNPs from transmission electron microscopy (TEM) images was determined to be 22 nm in diameter. XRD measurements showed that the crystallite sizes of the synthesised AgNPs were in the face-centred cubic crystal structure with an average size of 22 nm, which is consistent with TEM results. AA-AgNPs showed absorption at 435 nm, indicating that AgNPs exhibit a strong surface plasmon resonance (SPR) and play a role in stabilisation. AgNPs synthesised with Anchusa azurea flowers were observed using UV-vis spectroscopy to selectively and sensitively detect mercury ions (Hg2+). When Hg2+ in aqueous solution was added to the AgNPs, the overall absorbance dramatically decreased and the colour changed from yellow to colourless. This study shows that AA-AgNPs can be used as a cost-effective material in optical sensors for colorimetric determinations. [ABSTRACT FROM AUTHOR]

In this investigation, a nano-support containing cellulose nanocrystals – polydopamine (CP) was functionalized with glutaraldehyde (G) and utilized to immobilize papain. The properties of the supports and stabilized enzyme were characterized by TEM, SEM, DLS, Zeta-potential, FTIR, and EDS analyses. The optimal temperature of both papain forms was 60 °C, while the optimal pH value of the stabilized papain shifted from 7 to 8 after immobilization. The immobilized enzyme preparations showed higher stability at 80 and 90 °C and under acidic and alkaline conditions compared to the free enzyme. CPG-papain stability was higher than that of CP-papain. The K m values for free and immobilized papain on CP and CPG were 3.92, 3, and 2.74 mM respectively. K cat values were 9.05, 15.18, and 11.59 min−1 and catalytic efficiency values were 2.3, 5.05, and 4.23 mM−1.min−1. Additionally, the potential advantages of using a silver nanohydrid support were assessed. Although silver nanoparticles conveyed some catalytic activity to the final biocatalysts, they also caused a decrease in stability and activity of the immobilized papain. Therefore, the non-hybrid supports CP and CPG were more suitable candidates for the immobilization of papain than the hybrid supports. [Display omitted] • Cellulose nanocrystals – polydopamine support was synthesized. • Papain was covalently immobilized onto CP using glutaraldehyde. • Immobilizing the enzyme significantly enhanced its storage, thermal, and pH stability. • The K m kinetic parameter decreased while K cat /K m ratio increased. • The addition of AgNPs on the CP-papain worsened enzyme features [ABSTRACT FROM AUTHOR]

In this study, the antimicrobial activity of silver nanoparticles (AgNPs L21, AgNPs L22) produced using aqueous extracts of the Laser trilobum harvested in 2021 and 2022 was optimized. The experimental design and optimization of antimicrobial activity were performed using the response surface method (RSM). Using RSM, independent variables, such as silver concentration, extraction time, and synthesis temperature, were optimized as a result of the inhibition zone diameter against Staphylococcus aureus, Escherichia coli, Salmonella Typhimurium, and Listeria monocytogenes. Based on the optimization results, the extraction time, silver concentration, and temperature for AgNP L21 and L22 synthesis were determined to be 60 min, 5 mM, and 25 °C, respectively. When the XRD and TEM results of the nanoparticles synthesized under optimal conditions were evaluated, it was determined that the AgNPs were spherical in shape and had an average size of 30 ± 12 nm. Our study revealed that the year of harvest is unimportant for nanoparticles synthesized from L. trilobum, using a cheap and simple method that does not require toxic substances. Owing to the antimicrobial activity of nanoparticles produced under optimal conditions, it is possible to biocontrol and prevent contamination by these bacteria in food science and industry. [ABSTRACT FROM AUTHOR]

Since conventional antibiotics are almost ineffective on methicillin-resistant Staphylococcus aureus (MRSA) strains, designing their antibacterial alternatives is necessary. Besides, the use of vancomycin is applied for specific detection of the bacteria. Silver-incorporated vancomycin-modified mesoporous silica nanoparticles (MSNs@Van@Ag NPs) were designed for detection and treatment of MRSA bacteria. Mesoporous silica nanoparticles (MSNs) were synthesized through the template method, modified with vancomycin, and finally incorporated with silver nanoparticles (Ag NPs). The MSNs@Van@Ag NPs with a homogenously spherical shape, average size of 50-100 nm, surface area of 955.8 m2/g, and thermal stability up to 200°C were successfully characterized. The amount of Ag incorporated into the MSNs@Van@Ag was calculated at 3.9 ppm and the release amount of Ag was received at 2.92 ppm (75%) after 100 h. The in vitro antibacterial susceptibility test showed the MIC of 100 μg mL−1 for MSNs@Van and 50 μg mL−1 for MSNs@Van@Ag, showing in vitro enhanced effect of Ag and vancomycin in the bactericidal process. An in vivo acute pneumonia model was performed and biochemical assays and pathological studies confirmed the nanomedicine's short-term safety for in vivo application. Cytokine assay using ELISA showed that MSN@Van@Ag causes a reduction of pro-inflammatory cytokines and bacterial proliferation leading to alleviation of inflammatory response. [ABSTRACT FROM AUTHOR]

Considering the special effect of wound treatment in the field of medicine, antibacterial wound dressings preparation is one of the main challenges in successful wound healing. In this research, a starch (St)/polyvinyl alcohol (PVA) nanofiberous mat modified with graphene oxide (GO)-silver nanowire (AgNW) hybrid was fabricated. Initially, silver nanowires were synthesized by the polyol method, then GO-AgNW nanoparticle was prepared as a biocompatible and antibacterial biofilm. Reducing the diameter of nanofibers due to the addition of starch and GO-AgNW nanoparticles leads to fibroblast proliferation, increased collagen secretion, reduced inflammation and wound closure. Nanofibrous mats showed significant antibacterial activity against Staphylococcus aureus and Escherichia coli microorganisms. The largest zone of bacterial inhibition was obtained for Starch/PVA nanofibers containing 8% GO-AgNWs hybrid (27.11 and 24.62 mm). The use of GO-AgNW nanoparticles without drugs is an important point due to the strong antibacterial property of silver nanowire. The measured contact angle of nanofibrous mats was in the range of 57.8° as a desirable level of hydrophilicity for wound dressings. The degree of swelling obtained about 491.12%, and the water vapor transmission rate of 2549 ± 36 (g/m2.day) as a proof for accelerating wound healing. Finally, the results indicated that St/PVA/GO-AgNWs composite electrospun fibers could be a suitable candidate for the treatment of infectious wounds, surgical wounds, minor burns, etc. [ABSTRACT FROM AUTHOR]

Biosynthesized nanoparticles (NPs) have constituted the propitious future of nanomedicine because of biologically active plant secondary metabolites that are involved in green synthesis and due to their unique biological applications. This present study reports a simple, ecofriendly, sustainable, and cost-effective synthesis of silver nanoparticles (AgNPs) using the aqueous leaf extract of Limonium sinuatum with their antioxidant and antimicrobial properties. The biosynthesized L. sinuatum silver nanoparticles (Ls-AgNPs) were characterized using spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, x-ray diffraction (XRD), scanning electron microscopy (SEM), and zeta-sizer analysis. The morphology of the silver nanoparticles was investigated using x-ray diffraction and were spherical with diameters from 20 to 80 nm and a crystal structure identified to be face-centered cubic. The antioxidant activity of the biosynthesized nanoparticles was determined using 2,2-diphenyl-1-picryl-hydrazyl (DPPH). The result also reveals a high antimicrobial activity sensitive to E. coli. Resultantly, the study shows that the aqueous L. sinuatum water extract and the AgNPs both have good radical-scavenging abilities compared with L-ascorbic acid used as a positive control for testing their antiradical potency. [ABSTRACT FROM AUTHOR]

The current study concerns the valorization of waste rice hulls into value-added materials. To achieve this goal, first, the extraction route of mesoporous silica nanoparticles (SiO2NPs) from rice hulls using citric acid as a carbon template was compared with that prepared by conventional methods of incineration only. Both routes were performed at different temperatures of 600 and 700°C, and the fabricated SiO2NPs were studied by N2 physisorption isotherm, X-ray diffraction (XRD), Fourier transform infrared (FTIR), dynamic light scattering (DLS), and thermogravimetric (TG) analyses. The results show the influence of both routes and temperature on the porous structure, surface area, and charge of as-fabricated SiO2NPs. Furthermore, the physico-chemical features of as-prepared mesoporous SiO2NPs were utilized, in a facile and green way, to prepare silver NPs with high anti-microbial activity. The results were validated by the tools of UV-visible, FTIR, XRD, and XPS spectroscopy. Finally, the fabricated silver-doped mesoporous SiO2NPs were used as auxiliary additives through one-pot printing of different types of fabric (i.e., polyester (synthetic fabric), cotton (natural fabric), and cotton/polyester (blended fabric)). The EDX mapping of the pigment-printed fabrics with Ag-doped SiO2NPs exhibited the homogeneous distribution of Ag and Si atoms together with C and O throughout the fabric matrix. Interestingly, the pigment-printed fabrics with Ag-doped SiO2NPs demonstrated superior antibacterial activity, ultraviolet protection factor (UPF), and color characteristics in comparison to the conventional dyeing component. [ABSTRACT FROM AUTHOR]

The present study was focused on green synthesis of silver nanoparticles against pathogens of both gram-positive and gram-negative classes. Green synthesis of silver nanoparticles was successfully performed using Ziziana latifolia (ZL) Husk extract with the catalyst serving as sunlight. In making and stabilizing silver nanoparticles, the biomolecules present in the husk extract played the role of reducing and stabilizing agents. The resultant silver nanoparticles were characterized using UV–vis analysis, FTIR, HRTEM, SAD, EDAX, Zeta potential, and particle size analysis. In a DAPI study using the NIH 3T3 fibroblast cell line, ZL-AgNPS demonstrated outstanding stability and great biocompatibility. In vivo zebrafish toxicity and hemocompatibility experiments further indicated that the ZL-AgNPS were extremely biocompatible and safe. The novelty of this study is the synthesis of very stable silver nanoparticles in the aqueous phase by a single step reaction in sunlight without the use of any external stabilizing agent and reduction agent that the existing protocols do not require. The results showed that produced AgNPs are efficient against both microorganisms when the antibacterial activity of silver nanoparticles was compared to that of the pathogenic bacteria B. subtilis and E. coli. [ABSTRACT FROM AUTHOR]

The magnetite-silver nanocomposites (Fe3O4-Ag NCs) were synthesized via a facile and green process by Citrus sinensis peel extract. The deposition of silver nanoparticles (NPs) was confirmed by observing an absorption peak at the maximum wavelength at 422 nm in the suspension solution of samples, which is related to silver surface plasmon resonance (SPR). The characteristic diffraction patterns of Fe3O4 and Ag phases were characterized utilizing the XRD patterns and the average size of the crystals was 21 nm. The photocatalytic behavior of Fe3O4-Ag NCs was studied for the destruction of three organic dyes methyl green (MG), methyl orange (MO), and methylene blue (MB) below UV radiation. The effect of the amount of photocatalyst and volume of hydrogen peroxide as an oxidant in the process of dye degradation was also investigated. The complete degradation time of dyes MB, MG, and MO under UV irradiation in the presence of 0.002 g Fe3O4-Ag NCs were 57, 33, and 49 min, respectively. The time of degradation reactions showed the high photocatalytic performance of Fe3O4-Ag NCs. These results proved that the synergistic effect of magnetite in the role of supporting the silver NPs was a significant contribution to the excellent decolorization behavior of Fe3O4-Ag NCs. [ABSTRACT FROM AUTHOR]

Toll‐like receptor 4 (TLR‐4) ligands were initially shown to be the source of lipopolysaccharide (LPS), a gram‐negative bacterium's cell wall immunostimulatory component. Oxidative stress, apoptosis, and inflammation are all potential effects of LPS treatment on the lungs. By triggering oxidative stress and inflammation, these negative effects could be avoided. Robust flavonoid oleuropein (OLE) exhibits anti‐inflammatory, antiproliferative, and antioxidative properties. A nanodelivery system could improve its low bioavailability, making it more effective and useful in treating chronic human ailments. This study evaluates the effects of AgNP‐loaded OLE on LPS‐induced lung injury in rats in terms of TLR4/P2X7 receptor‐mediated inflammation and apoptosis. Forty‐eight male albino rats were randomly divided into eight groups. Drugs were administered to the groups in the doses specified as follows: Control, LPS (8 mg/kg ip), OLE (50 mg/kg) AgNPs (100 mg/kg), OLE + AgNPs (50 mg/kg), LPS + OLE (oleuropein 50 mg/kg ig + LPS 8 mg/kg ip), LPS + AgNPs (AgNPs 100 mg/kg ig + LPS 8 mg/kg ip), and LPS + OLE + AgNPs (OLE + AgNPs 50 mg/kg + LPS 8 mg/kg ip). After the applications, the rats were decapitated under appropriate conditions, and lung tissues were obtained. Oxidative stress (SOD, MDA, and GSH), and inflammation (IL‐6, IL‐1β, TNF‐α, Nrf2, P2X7R, AKT, and TLR4) parameters were evaluated in the obtained lung tissues. Additionally, histopathology studies were performed on lung tissue samples. The data obtained were evaluated by comparison between groups. Both OLE and OLE + AgNPs showed potential in reducing oxidative stress, inflammation, and apoptosis (p < 0.05). These findings were supported by histopathological analysis, which revealed that tissue damage was reduced in OLE and OLE + AgNPs‐treated groups. According to the results, LPS‐induced lung injury can be reduced by using nanotechnology and producing OLE + AgNP. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) and Zinc oxide nanoparticles (ZnONPs) have been widely used and are eventually been discharged into the natural aquatic ecosystem. The current study examined and correlated the toxicity of AgNPs and ZnONPs on the Mozambique tilapia, Oreochromis mossambicus. Lethal concentration (LC50) was determined with four different concentrations (0.05, 0.10, 0.15, and 0.20 mg/L) of AgNPs and ZnONPs; subsequently, the fishes were exposed to sublethal concentrations for a period of 21 days, and the oxidative stress and antioxidant and nonantioxidant parameters were studied. Results revealed oxidative stress evinced by increased lipid peroxidation (LPO) protein carbonyl activity (PCA), glutathione‐S‐transferase (GST), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT) activity, metallothionein (MT) activity, and reduced glutathione in chronic exposure compared with acute exposure. Nonspecific immunological characteristics such as lysozyme (LYZ), myeloperoxidase (MPO), and respiratory burst activity (RBA) were also noticed in the serum. Furthermore, severe histological damages including damages in telangiectasia and epithelial cell hyperplasia were found in the combined treated group with Ag and ZnONPs than in individual treatments. When Ag and ZnONPs were combined, a reduction in the accumulation of Ag was observed in the liver, which increased drastically in individual exposure. The current findings highlight the importance of taking into account the combined exposure and correlation of NPs, their bioavailability, and toxicity in the aquatic ecosystem. [ABSTRACT FROM AUTHOR]

In recent years, there has been an exponential increase in the production of silver bionanoparticles due to their widespread commercialization and technological applications. However, there is limited understanding of the impact of silver bionanoparticles on biological agents commonly used in wastewater treatment, particularly in waste stabilization ponds (WSPs). This study aimed to synthesize new silver nanoparticles (sg-AgNPs) from Synadenium glaucescens root using an environmentally friendly method and optimized biosynthesis parameters, and evaluate their antimicrobial activity and ecotoxicological impact on WSPs using standardized approaches. The average primary sizes of the sg-AgNPs in the five samples were not significantly different (P > 0.05), indicating the effectiveness of the eco-friendly method and the importance of optimal biosynthesis conditions. Analysis from UV–Vis spectroscopy, energy-dispersive spectroscopy (EDX), transmission electron microscope (TEM), and X-ray diffraction (XRD) confirmed that sg-AgNPs exhibited typical characteristics of green silver nanoparticles. Furthermore, sg-AgNPs showed strong antimicrobial activity (MIC, 0.012–0.094 mg/ml) against gram-positive bacteria (Escherichia coli), gram-negative bacteria (Staphylococcus aureus), non-filamentous fungi (Candida albicans) and filamentous fungi (Aspergillus niger). While the Synadenium glaucescens root proved to be a valuable precursor for producing effective antimicrobial sg-AgNPs, the introduction of sg-AgNPs into WSPs significantly impacted algal chlorophyll-a production and survival of ostracod population. These results shed light on the ecotoxicological risks of sg-AgNPs for WSPs organisms and highlight the suitability of algae and ostracods as model organisms for ecotoxicological studies in WSPs. [ABSTRACT FROM AUTHOR]

This study investigates the resistive switching characteristics of Ag nanoparticle (AgNP)-incorporated pectin (pectin-AgNP) as a memristive thin film, with varying concentrations of AgNP (0.0 wt.%, 0.5 wt.%, and 1.0 wt.%) and pectin (5.0 mg/L, 5.5 mg/L, 6.0 mg/L, 6.5 mg/L, and 7.0 mg/L), sandwiched between Au and indium tin oxide (ITO) electrodes on glass substrate. The structural, chemical, and electrical properties of these pectin-AgNP thin films were evaluated. With AgNP concentration of 0.5 wt.% in a pectin concentration of 5.5 mg/mL, the Fourier transform infrared (FTIR) spectra indicated the highest presence of C–O bonds. This suggests the incorporation of AgNP and the formation of more linear and extended pectin chains established by glycosidic bonds. The abundance of C–O bonds contributed significantly to the increase in the resistance of the thin film, consequently yielding the highest ON/OFF ratio (7.2 × 103) observed among the samples. The electronic and thermochemical mechanisms governing the resistive switching behaviours were also proposed. [ABSTRACT FROM AUTHOR]

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Nanotechnology is a multidisciplinary and innovative area, gaining world-wide attention due to its large applications in remediation of pollutants. Nanotechnology is a significant technique for implementing clean, non-hazardous, and environment friendly remediation approaches, because of their nano size and large surface area. The majority pollutants include heavy metals, petrochemicals, hormones, endocrine disruptors, and synthetic dye, pose a serious threat to humans and environment. The conventional approaches are costly, time-consuming, and labor-intensive, for effectively removing emerging pollutants. Therefore, the present review suggested the applications of nanotechnology by taking nanocatalysis and nanoadsorption process to highlight the shortcomings of traditional methods. Moreover, we discuss the nanomaterials including silver nanoparticles, dendrimers, carbon nanotubes, and quantum dots etc. as an effective alternative which can increase the sustainability of the applied technology. By exploring current research, this article aims to provide a comprehensive foundation for nano-based approaches, its related challenges and environmental concerns that enhance our understanding of nanomaterials properties and its related hurdles. This article also provides an overview of scientific insight of advanced nanomaterials with main focus given to mechanisms of remediation and demonstrates how recent developments in nanotechnology hold great promise for addressing a number of pressing issues in environmental research. [ABSTRACT FROM AUTHOR]

Introduction: This study explores potential application of silver nanoparticles (AgNPs) to treat periodontal infection using Azadirachta indica leaf extract. The eco-friendly green synthesis process uses Azadirachta indica as a natural stabilizer and reducer, allowing AgNPs to be formed. Methods: Experimental AgNPs were characterized through transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), Zeta potential, ultraviolet-visible spectroscopy (UV-Vis) etc. The antimicrobial, antioxidant potential of AgNPs was tested to identify its efficacy against periodontal infections. Results and discussion: AgNPs were found spherical, nanosized (86 nm), with negative surface charge (−26.9 mV). TEM study depicted clear formation of discrete nanosize particles with smooth surface texture. Results showed strong antibacterial and anti-oxidant action of experimental AgNPs, preventing biofilm growth and bacterial viability. A higher binding affinity was observed between Quercetin and the selected protein, which is implicated in bacterial growth and biofilm formation on teeth. The study suggests that Azadirachta indica derived AgNPs could be a safe, efficacious, and eco-friendly alternative in place of conventional therapies to treat periodontal infection. Future in vivo studies are however warranted. [ABSTRACT FROM AUTHOR]

This research aims to develop a novel approach, employing cold plasma technology for preparing nanoparticles of silver oxide by Anethum graveolens (dill) leaf extract as a natural reducing agent. This investigation evaluated the properties of antibacterial and antibiofilm-prepared nanoparticles. Initially, dill leaf extract was prepared to stabilize and reduce the size of silver oxide nanoparticles. Improved synthesis and optimal conditions for nanoparticle formation were achieved through the application of cold plasma technology. The results obtained showed that the prepared silver oxide nanoparticles have strong antibacterial properties and that they have antibacterial activity against a different group of bacteria that cause diseases such as Klebsiella pneumoniae (K. pneumoniae), Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The results also showed the effectiveness of nanoparticles in preventing the formation of bacterial biofilms, as the highest rate of inhibition was for gram-positive bacteria S. aureus. This study demonstrated the effectiveness of plant extracts and cold plasma technology when combined in producing nanoparticles with improved properties, which may push toward the employment of these materials in developing innovative and sustainable solutions in various scientific and applied fields. [ABSTRACT FROM AUTHOR]

Pathogen-induced infections and the rise of antibiotic-resistant bacteria, such as Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), pose significant global health challenges, emphasizing the need for new antimicrobial strategies. In this study, we synthesized graphene oxide (GO)-based composites functionalized with silver nanoparticles (AgNPs) and copper nanoparticles (CuNPs) as potential alternatives to traditional antibiotics. The objective is to assess the antibacterial properties of these composites and explore their efficacy against E. coli and S. aureus, two common bacterial pathogens. The composites are prepared using eco-friendly and conventional methods to ensure effective nanoparticle attachment to the GO surface. Structural and morphological characteristics are confirmed through SEM, AFM, EDS, XRD, UV-vis, FTIR, and Raman spectroscopy. The antibacterial efficacy of the composites is tested through disk diffusion assays, colony-forming unit (CFU) counts, and turbidimetry analysis, with an emphasis on understanding the effects of different nanoparticle concentrations. The results demonstrated a dose-dependent antibacterial effect, with GO/AgNP-1 showing superior antibacterial activity over GO/AgNP-2, particularly at lower concentrations (32.0 μg/mL and 62.5 μg/mL). The GO/CuNP composite also exhibited significant antibacterial properties, with optimal performance at 62.5 μg/mL for both bacterial strains. Turbidimetry analysis confirmed the inhibition of bacterial growth, especially at moderate concentrations, although slight nanoparticle aggregation at higher doses reduced efficacy. Lastly, both GO/AgNP and GO/CuNP composites demonstrated significant antibacterial potential. The results emphasize the need to fine-tune nanoparticle concentration and refine synthesis techniques to improve their efficacy, positioning these composites as strong contenders for antimicrobial use. [ABSTRACT FROM AUTHOR]

In this study, a red seaweed (Solieria robusta) containing ι‐carrageenan (Carr) was used for nanoparticles (NPs) synthesis using silver (Ag) ions. Initially, the ι‐Carr was extracted from S. robusta using the alkali method. The Carr extracted was fractionated into 3 fractions and > 14 kDa fraction showing high yield with maximum sulfate content characterized using Fourier transform infrared (FT‐IR) as ι‐Carr was used for AgNPs synthesis. The synthesized CarrAgNPs were again used for curcumin (Cur) encapsulation. The cytotoxicity of Carr, Cur, CarrAgNPs, and CurCarrAgNPs was evaluated using HeLa cell lines by MTT assay. The CarrAgNPs and CurCarrAgNPs were characterized using UV‐visible spectroscopy, as well as FT‐IR and XRD analysis. The UV‐visible spectrum confirms the CarrAgNPs showing characteristic SPR bands recorded between 344 and 490 nm with broad peak at 430 nm. The shape of the NPs is spherical, arranged in order of seven per chain. The XRD and FT‐IR characteristics confirm the orthorhombic crystal structure of these NPs. Remarkably, Cur‐loaded CarrAgNPs demonstrate potent anticancer properties by maximum reduction of HeLa cell viability after 24 h at 200 μg/mL in pH 7.4 in an MTT assay medium. A significant increase in the cancer cell viability was recorded at high concentrations of CurCarrAgNPs, confirming its less diffusion and dissolution properties and bioavailability due to lipophilic Cur encapsulation, whereas cytotoxicity was increased proportionately by increasing concentrations of Cur, Carr, and CarrAgNPs that confirm a direct relation with size, dissolution, and bioavailability recorded on the basis of cell death in 24 h of introduction at pH 7.4. The cytotoxicity results suggest the potential of Cur, Carr, CarrAgNPs, and CurCarrAgNPs for drug delivery in selective biomedical product developments. This study highlights the versatility and effectiveness of CurCarrAgNPs in cancer therapy by enhancing the efficacy of therapeutic interventions and targeted drug delivery. [ABSTRACT FROM AUTHOR]

ABSTRACT Nanoparticles (NPs) are well‐known biostimulants in plant biotechnology, utilised to enhance the physical properties of plants and exhibit positive effects on them. The important key role is the most suitable type, effective dose and size of NP to be used in plant tissue culture systems. In this study, various concentrations of silver nanoparticles (AgNPs; 0, 25, 50, 75 and 100 μg L−1) were tested as elicitors in callus culture with the aim of enhancing secondary metabolite production in lemon balm (Melissa officinalis L.). According to the results obtained, callus formation rates have shown an increase in all applications compared to the control group. The highest callus formation, weight and diameter were observed in 50 μg L−1 application. In this application, the callus structure was compact and its colour was green. However, the aromatic compounds, neral and geranial increased significantly in 25 μg L−1 application. The maximum increase in phenolic compounds such as caffeic acid, chlorogenic acid, proto‐catechic acid, hesperidin and p‐coumaric acid was observed in the 75 μg L−1 AgNP and the highest increase in rosmarinic acid compound was determined in the 50 μg L−1 application. The study found that AgNP applications are an effective method for increasing the production of secondary metabolites in medicinal and aromatic plants, such as lemon balm, in vitro. [ABSTRACT FROM AUTHOR]

Due to drug‐resistant bacteria, antimicrobial composite materials that will replace antibiotics are among the current research topics. In this study, environmentally‐friendly, low‐cost, easy‐to‐synthesize chitosan/silk sericin/silver nanoparticles (Cht/SS/AgNPs) membranes were obtained for use in antibacterial applications. For material synthesis, firstly, AgNPs were obtained by mixing solution of 2 % sericin (at pH 11)‐10 mM AgNO3 at 100 °C with hydrothermal method and AgNPs formation was confirmed by UV‐Vis measurements. Then, sericin/AgNPs solution was added to chitosan solutions at different ratios and Cht/SS/AgNPs composites were obtained by solvent casting method. The final forms of the membranes were characterized by fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM)‐energy dispersive X‐ray spectroscopy (EDS), and thermogravimetric analysis (TGA). Water retention capacities and mechanical properties of the membranes were also determined. Finally, antibacterial and biocompatibility properties were evaluated by disc diffusion test method on Escherichia coli and Staphylococcus aureus and MTT on L929 fibroblast cell line, respectively. The obtained membranes had homogeneous appearance, high swelling ratios, good mechanical properties. The composites also showed excellent antibacterial activity, especially on S. aureus and good biocompatibility. In summary, Cht/SS/AgNPs composites can be used as an alternative polymeric antibacterial materials especially as the wound‐dressing materials or functional packaging materials. [ABSTRACT FROM AUTHOR]

Green synthesized silver nanoparticles (AgNPs) have received lots of attention due to being used as potential therapeutic agents. For the first time, this research investigated the biosynthesis of silver nanoparticles using the extract of Daphne mucronata seeds, which are rich in phenolic and polyphenolic substances and evaluated their antibacterial, antifungal, and scavenging activities. The process of nanoparticle (NPs) preparation was confirmed using UV–vis spectroscopy with an absorption peak at a wavelength of 440 nm. Dynamic light scattering (DLS) was used to determine the particles' distribution. Fourier‐transform infrared spectroscopy (FTIR) validated the functional groups contributing to the reduction of Ag+ to Ag. Moreover, X‐ray diffraction analysis (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) approved the crystalline nature and spherical shape of the particles with mean and standard deviation of particle size to be 60.25 and 24.88 nm, respectively. The antibacterial, antifungal, and scolicidal activities of AgNPs were studied using disc diffusion against four standard bacteria species and microdilution methods for four Candida strains. The greatest effect of AgNPs with the highest concentration (80 µg/mL) was observed on Staphylococcus aureus (22.26 mm) and the lowest on Pseudomonas aeruginosa (19.07 mm). In the case of Candida fungus, the highest effect of AgNPs was reported for Candida krusei (7.93 µg/mL) and the lowest for Candida albicans (63.49 µg/mL). Also, these nanoparticles were able to register 100% lethality on the Echinococcus granulosus parasite in 15 min at a concentration (80 µg/mL). Therefore, the production of AgNPs as a renewable and cheap material can be effective after performing all the necessary tests as antibacterial, antifungal and antiparasitic agents with the least side effects in biomedical and pharmaceutical sciences. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) have gained attention for their unique properties and potential applications, particularly in medicine. This study aim to investigate the green synthesis of silver and copper nanoparticles (NPs) using Parthenium hestephorus extract and evaluate their biological activities. The synthesized NPs were characterized using various analytical techniques, such as UV‐Vis spectroscopy, which confirmed the successful synthesis of silver and copper nanoparticles, with characteristic absorption peaks observed at 450 nm and 580 nm, respectively. Fourier‐transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), scanning electron microscopy (SEM), and energy‐dispersive X‐ray spectroscopy (EDX) were also conducted. In antimicrobial evaluations, the silver and copper nanoparticles exhibited notable inhibitory zones ranging from 12–18 mm against Staphylococcus aureus and 27–30 mm against Escherichia coli bacteria. Furthermore, the nanoparticles' potential as anticancer agents were tested on HepG2 human cancer cells using the MTT assay. The silver, copper nanoparticles, and control exhibited dose‐dependent cytotoxicity, with IC50 values of 35 μg/mL, 50 μg/ml, and 30 μg/ml, respectively, suggesting their promise in cancer treatment. Antioxidant activity was demonstrated through free radical scavenging assays, with silver and copper nanoparticles showing significant potential, inhibiting free radicals by 80 %, 70 %, and 90 %, respectively. It is concluded that the green synthesis of silver and copper nanoparticles using extract of Parthenium hestephorus presents an efficient and sustainable method for generating NPs with potent antibacterial, anticancer, and antioxidant capabilities. [ABSTRACT FROM AUTHOR]

Fish-borne zoonotic trematodes (FBZTs) pose significant health risks and economic challenges worldwide. This study investigated the prevalence of encysted metacercariae (EMCs) in Nile tilapia (Oreochromis niloticus) from two Egyptian governorates and evaluated the antiparasitic efficacy of chitosan, silver, and selenium nanoparticles against these parasites. A cross-sectional analysis of 453 O. niloticus specimens revealed an overall EMC prevalence of 40.8%, with infection rates of 34.11% in Giza and 49.5% in Dakahlia. Clinostomid and Prohemistomid metacercariae were the most common, with mixed infections observed. Transmission electron microscopy characterized the synthesized nanoparticles, showing average diameters of 9.6–18.7 nm for chitosan, 13.2–19.8 nm for selenium, and 11.7–15.1 nm for silver nanoparticles. In vitro antiparasitic assays demonstrated varying efficacies among the nanoparticles. Against Clinostomum spp. metacercariae, chitosan nanoparticles showed the highest potency, achieving LC50 at 66 μg/ml after 30 min and LC90 at 100 μg/ml after 120 min. For Prohemistomum vivax EMCs, chitosan nanoparticles exhibited superior efficacy, achieving LC50 at 8 μg/ml after 1 h and LC90 at 16 μg/ml after 2 h. Silver and selenium nanoparticles showed lower efficacy for both parasite species. Scanning electron microscopy revealed significant ultrastructural damage to the parasite tegument following nanoparticle exposure, including disappearance of transverse ridges, integument shrinkage, and formation of blebs. This study provided valuable insights into the prevalence of FBZTs in Egyptian Nile tilapia and demonstrated the potential of nanoparticles, particularly chitosan, as effective antiparasitic agents. These findings pave the way for developing novel, targeted strategies to control fish-borne zoonotic trematodes, potentially reducing their impact on public health and aquaculture economies. [ABSTRACT FROM AUTHOR]

Nanoparticles synthesized from green sources have attracted great recognition in the present times, which can be ascribed to their distinctive attributes and diversified applicability. Therefore, the present study employed Ocimum basilicum seed extract to synthesize silver nanoparticles. UV–vis spectrophotometry revealed strenuous peaks for different concentrations of silver nanoparticles ranging between 400 and 430 nm. The average crystal size calculated using X-ray diffraction analysis was 6.7 nm. Energy-dispersive X-ray analysis clearly displayed the presence of silver ions in the elemental structure of the synthesized nanoparticles. The morphology of synthesized nanoparticles revealed by scanning electron microscopy was documented in terms of spherical shape surrounded by an organic layer and nanoparticle size was estimated to be in between 10 and 80 nm. The nanoparticles exhibited substantial antibacterial activity against 46 foodborne bacterial isolates and 15 clinical isolates of Klebsiella pneumoniae, with the largest inhibition zones measuring 24 and 13 mm, respectively. Minimum inhibitory concentration values ranged between 500 and 800 µl/ml for various isolates. The antibacterial effect of all antibiotics revealed considerable enhancement when combined with nanoparticles. The calculated fractional inhibitory concentration index values were < 1 validating excellent synergism between nanoparticles and all antibiotics except ciprofloxacin against the majority of bacterial isolates. Interestingly, the biogenic nanoparticles showed significant antioxidant potential with IC50 value of 165 µg/ml as well as anti-inflammatory activity with an IC50 value of 82 µg/ml. Conclusively, the seed extract of Ocimum basilicum can be prospected for the development of antibacterial silver nanoparticles against pathogenic bacteria. [ABSTRACT FROM AUTHOR]

The localized surface-plasmon resonances of coinage-metal clusters and nanoparticles enable many applications, the conception and necessary optimization of which require precise theoretical description and understanding. However, for the size range from few-atom clusters through nanoparticles of a few nanometers, where quantum effects and atomistic structure play a significant role, none of the methods employed previously has been able to provide high-quality spectra for all sizes. The main problem is the description of the filled shells of d electrons which influence the optical response decisively. We show that the DFT+U method, employed with real-time time-dependent density-functional theory calculations (RT-TDDFT), provides spectra in good agreement with experiment for silver clusters ranging from 4 to 923 atoms, the latter representing a nanoparticle of 3 nm. Both the electron-hole-type discrete spectra of the smallest clusters and the broad plasmon resonances of the larger sizes are obtained. All calculations use the value of the effective U parameter that provides good results in bulk silver. The agreement with experiment for all sizes shows that the U parameter is surprisingly transferable. Our results open the pathway for calculations of many practically relevant systems including clusters coupled to bio-molecules or to other nano-objects. Calculating optical properties and surface plasmons of nanoclusters of different sizes is essential but challenging. Here the authors obtain good spectra for sizes from 4 atom silver clusters to 3-nm nanoparticles using the TDDFT+U method with constant U. [ABSTRACT FROM AUTHOR]

We synthesized the silver‐decorated copper microsphere via the hydrothermal method followed by photoreduction of silver ions. Sub 100 nm Ag nanoparticles anchored on the surface of Cu microspheres enhance the electrochemical performance and the selectivity of the CO2 reduction into CH4. Incorporating Ag nanoparticles onto Cu lowers the charge transfer resistance, enhancing the catalyst's conductivity and active site and increasing the rate of CO2 reduction. The faradaic efficiency of silver nanoparticles decorated copper microsphere for methane was 70.94 %, almost twice that of a copper microsphere (44 %). The electrochemical performance showed higher catalytic properties, stability, and faradaic efficiency of silver‐decorated copper microspheres. [ABSTRACT FROM AUTHOR]

This article aims to investigate the hall current consequences on the transfer of clean water containing silver in addition to copper nanoparticles suspended nanofluids through vertical rotating channel. Boussinesq approximation is taken into consideration. Exact analytical solutions of governing equations subject to physical boundary conditions are obtained using the techniques of non‐dimensionalization. The impacts of Grashof number, radiation parameter, Prandlt number, frequency parameter, magnetic parameter, Hall parameter, parameter of rotation and its effects on primary as well as secondary velocity and temperature profiles are presented graphically. We analyze the Hall effects and mixed convection in magnetohydrodynamic (MHD) flow of nanofluids through a vertical rotating channel, based on extensive research and applications. An analytical approach is used to derive the exact solution to this problem. A comparative study for silver and copper nanoparticles is made. A tabular solution for impacts of said parameters on convection rate and skin friction coefficient is also presented. This study is applicable for geophysical dynamics and engineering applications. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance (SPR)-based biosensors have gained increasing prominence due to their ability to provide fast, accurate and real-time results. The functionalization of the SPR sensor chip is essential to ensure the effective binding of recognition biomolecules, making it a crucial step in the efficient construction of biosensors. We demonstrate here the functionalization of the SPR sensor chip with inorganic–organic nanocomposites formed by poly(amidoamine) dendrimers and silver nanoparticles (AgDENs). Several techniques were employed to characterize the structure and morphology of the nanocomposites. Silver nanoparticle/dendrimer structures with a size distribution between 3.7 and 16.2 nm were obtained, and chemical interactions were found between the amide groups of the dendrimers and the silver nanoparticles. Afterward, the synthesized AgDENs were combined with cysteamine using the layer-by-layer (LbL) technique to create multivalent films on the SPR sensor chip. To assess the versatility of these molecular assemblies in the biomaterial anchoring process, studies involving the immobilization of different types of proteins, including the Chaperone CHIP protein (carboxyl terminus of the Hsc70-interacting protein), heat shock cognate protein 70 (Hsc70), Free Candida antarctica lipase B (CALB L), and a recombinant protein (C1 protein) from the protozoan Leishmania infantum to the AgDENs were conducted. To evaluate a specific application, an immunosensor was constructed by anchoring the C1 protein on the proposed platform (AgDENs) to selectively detect Leishmania infantum antibodies in canine serum samples from positive and negative groups for visceral leishmaniasis. In brief, the nanostructured materials composed of poly(amidoamine) dendrimers and silver nanoparticles proved to be effective in anchoring different biological recognition elements, demonstrating their versatility for biosensor applications. An increase in sensor interface sensitivity was observed, likely due to the coupling of localized surface plasmons of silver nanoparticles with the plasmon of the flat Au. The large surface area of the film, combined with its excellent chemical stability, shows that the proposed platform is a very interesting strategy in biosensing. [ABSTRACT FROM AUTHOR]

Currently, research in the development of high-performance sensing platforms has increased to fulfill the needs of analysis and detection. In this study, we developed a novel type of surface-enhanced Raman scattering (SERS) chip composed of a covalent organic framework (COF)-silver nanoparticles (AgNPs) nanocomposite, and this nanocomposite was fabricated by a one-step method of ultrasonically mixing the obtained COF and AgNPs. The fabricated chip exhibited high sensitivity and repeatable SERS effects. Practical application results showed that the chip was highly sensitive and reliable and capable of detecting DNA bases (adenine) to fit an equation in the range from 0.01 pM to 1 nM, with an R-square of 0.97253 and a detection limit of ~0.026 pM (signal-to-noise ratio (S/N) = 3). Therefore, the proposed SERS system has potential applications in biological assays. Schematic of AgNP@COF as SERS substrates for the detection of DNA bases. [ABSTRACT FROM AUTHOR]

Background: To compare the impacts of different remineralizing agents on demineralized enamel, we focused on chitosan nanoparticles (ChiNPs) and silver nanoparticles (AgNPs). Methods: This study was conducted on 40 extracted human premolars with artificially induced demineralization using demineralizing solution. Prior to the beginning of the experimental procedures, the samples were preserved in artificial saliva solution. The nanoparticles were characterized by transmission electron microscopy (TEM) and teeth were divided into four equal groups: Group A was utilized as a control group (no demineralization) and received no treatment. Group B was subjected to demineralization with no treatment. Group C was subjected to demineralization and then treated with ChiNPs. Group D was subjected to demineralization and then treated with AgNPs. The teeth were evaluated for microhardness. The enamel surfaces of all the samples were analysed by scanning electron microscopy (SEM) for morphological changes and energy dispersive X-ray analysis (EDX) for elemental analysis. Results: The third and fourth groups had the highest mean microhardness and calcium (Ca) and phosphorous (P) contents. SEM of these two groups revealed relative restoration of homogenous remineralized enamel surface architecture with minimal micropores. Conclusion: Chitosan nanoparticles (NPs) and silver NPs help restore the enamel surface architecture and mineral content. Therefore, chitosan NPs and AgNPs would be beneficial for remineralizing enamel. [ABSTRACT FROM AUTHOR]

Background: The purpose of the study was to evaluate the effect of adding mesoporous silica with silver nanoparticles to conventional glass ionomer cements (GIC) on its, physical, chemical, mechanical properties and ion release analysis. Methods: Synthesized mesoporous silica with silver nanoparticles were added in 1, 3 and 5% by weight to the liquid component of GIC forming three experimental groups and compared with plain GIC as control group. Physical and chemical characterization were conducted using nano-computerized tomography (NanoCT) and Fourier transform infrared spectroscopy. Surface microhardness, water sorption and solubility were analyzed. Ion release was investigated using Inductive Coupled Plasma-Optical Emission Spectroscopy and High Performance Liquid Chromatography. Statistical analysis between different groups for the set parameters using parametric and non-parametric tests. The results were analysed using one way analysis of variance (p < 0.05). Results: Synthesized mesoporous silica with silver nanoparticles were of 7.28 ± 5.0 nm in diameter with a spherical morphology. NanoCT revealed less porosities for 3 wt %. Microhardness showed a statistically significant difference for 5 wt% at day 1 and 21 (p < 0.0001). Water sorption values decreased significantly on day 14 compared to day 7 for control, 1, 3 and 5 wt%. Control specimens showed highest concentration of fluoride release followed by 5, 3 and 1 wt%. Conclusion: Mesoporous silica with silver nanoparticles modified glass ionomer cements showed comparable microhardness to conventional GIC. Ion release was evident from the modified specimens. Silver remained within the GIC for atleast four weeks following incorporation. [ABSTRACT FROM AUTHOR]

Nanotechnology and nanoscience are due to their numerous uses in medicine, engineering, and water pollution sensors and their expanding research fields. In this study, the essential oil, methanolic extract, and biosynthesized silver/silver oxide nanostructures (Ag/AgO NSs) using the aqueous extract of the plant were prepared. The phytochemical compounds of the extract and essential oil were analyzed using gas chromatography/mass spectrometry (GC/MS), respectively. The GC/MS technique identified 34 compounds in the essential oil of the plant with the major constituents including oleic acid (18.5%), palmitic acid (11.08%), phytone (6.64%), p-vinylguaiacol (6.4%), and phytol (4.23%). After the phytochemical identification, the total flavonoid and polyphenol contents of the extract was determined, too. Prodelphinidin B3 compound in the Malva sylvestris extract was analyzed and detected by high-performance liquid chromatography/ultraviolet detector (HPLC-UV), at a retention time of around 10 min. In addition, M. sylvestris extract was used for green synthesis of Ag/AgO NSs. The as-prepared NPs were characterized using X-ray diffraction (XRD), UV-visible absorption spectroscopy, scanning electron microscope equipped with energy-dispersive X-ray spectroscopy (SEM/EDS), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH), and Fourier transform infrared (FT-IR) analyses. Surface plasmon resonance (SPR) absorption at λmax 320 nm in the UV-vis spectra confirms the formation of Ag/AgO NSs. The crystalline structure of Ag/AgO NSs was confirmed by XRD analysis. The nanoparticles were found to have a small size, measuring 64.16 nm, 44.33 nm, and 50 nm using the Williamson-Hall, Scherrer, and SEM/EDS methods, respectively. Besides, that spherical shape of Ag NPs with good size distribution was observed in the SEM/EDS analysis. The small size, around 50 nm, and spherical shape of Ag/AgO NSs with good size distribution were observed in the SEM/EDS analysis. Besides, the antibacterial activity of the extract was evaluated against three pathogenic bacteria, by disk diffusion method. Significant antibacterial activity was observed for the prepared extracts of M. sylvestris against the bacteria (Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa), and the results were compared with the known antibiotics such as amoxicillin, cephalexin, erythromycin, and fluconazole. [ABSTRACT FROM AUTHOR]