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Antibiotic success rates are decreasing as drug-resistant bacteria become more prevalent, prompting the development of new therapeutic drugs. Herein, we demonstrated the antimicrobial activity of sarsaparilla root extract fabricated silver nanoparticles (sAgNPs). The UV–Visible spectra revealed that the surface Plasmon resonance maxima of sAgNPs were at 415 nm. Transmission electron microscopy confirms that the particles are spherical with size of 12–35 nm. The minimum inhibitory concentration (MIC) of sAgNPs against Escherichia coli, uropathogenic Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus was 62.5, 62.5, 62.5, 62.5, 125 and 125 µM, respectively. At 1X MIC, sAgNPs induces excess reactive oxygen species (ROS) production and disturbs the bacteria membrane intergity, causing cytoplamic membrane depolarization. Interestingly, antibacterial activity of sAgNPs was considerably reduced in the presence of an antioxidant, N-acetyl cysteine, suggesting that ROS-induced membrane damage is a plausible cause of cell death. In contrast to many studies that only report the in vitro activity of NPs, we determined the in vivo antibacterial efficacy using the zebrafish model. It was found that sAgNPs protect fish from infection by inhibiting bacterial growth and eliminating them from the fish. In addition, the catalytic potential of sAgNPs for wastewater decontamination was demonstrated by degrading organic pollutants such as methyl orange, congo red, reactive black, and acid blue. The pollutants degraded in less than 10 min, and the reaction follows pseudo-first-order kinetics. As a proof of concept, the catalytic potential of sAgNPs in degrading mixed dyes to satisfy industrial wastewater treatment needs was established. In summary, sAgNPs have the potential to act as nanocatalysts and nano-drugs, addressing key challenges in medical and environmental research. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles (Ag NPs) dispersed in deionized water (DW) are prepared using the Nd:YAG laser ablation method. Transmission electron microscopy (TEM) results were used to investigate the shape and particle size of Ag NPs. The spherical shape and size of about 30 nm are characterized. X-ray diffraction (XRD) analysis shows a good crystallinity of Ag NPs and distinguished peaks at 38° without any impurities. The optical properties of Ag NPs were studied by a UV–visible spectrophotometer, and the surface plasmon resonance was observed at an excitation wavelength of about 402 nm and a direct band gap of about 2.25 eV. The results of the inhibitory activity against Lactobacillus and Streptococcus mutans bacteria indicated areas of high inhibition. The highest inhibition zone was 19 mm at the stock concentration. The anticancer properties of Ag NPs were studied with multi-concentration; the small particle size of Ag NPs led to the killing of about 70% of the MCF-7 line; and the inhibitory concentration (IC50) of Ag NPs was about 93.55 µg/mL−1. [ABSTRACT FROM AUTHOR]

With the demand for better chronic wound care, the clinical problem of managing wound infections has already reached a critical level. Therefore, the development of novel antibiotic-free wound dressings is essential for wound care. The proteolytic enzyme bromelain, silver nanoparticles (AgNPs), and bromelain loaded on silver nanoparticles (Br-AgNPs) were assessed for their impact on wound healing in the albino mice. The formulated nanoparticles were characterized using different techniques, i.e., ultraviolet (UV), Fourier transform infrared (FTIR), and X-ray diffraction (XRD) analysis. The antibacterial and fungal activities of the formulated nanoparticles were also investigated. After 5 days of treatment, the wound healing progression and wound size reduction rate were monitored. In addition, serum and skin tissue samples were collected to assess the changes in inflammation levels and observe the histological changes. The results indicated a spherical shape and regular distribution of the synthesized gold nanoparticles, with an average particle size of 41.33–61.30 nm, where the size was about 39.84 and 82.91 nm after loading bromelain. The Br-AgNPs were the most active antimicrobial agents against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Candida albicans, as compared to the other samples and positive controls. The fibronectin and collagen III levels were significantly increased in the animal groups treated with bromelain and Br-AgNPs (7132.52 ± 324.67 and 7006.00 ± 565.19 pg/ml, respectively), compared to the negative control group. Moreover, wound closure was significantly enhanced in the Br-AgNP-treated animals compared to the other treated and control groups. The histopathological analysis supported the wound healing potential of the Br-AgNPs through their ability to induce dense fibrous connective tissue in the wound area, which was rich in irregular bundles of collagen fibers and interspersed with numerous fibroblasts. The present findings could provide valuable insight into how Br-AgNPs can accelerate wound healing, reduce recovery time, and provide an antimicrobial barrier for wounds. [ABSTRACT FROM AUTHOR]

This study explores the biosynthesis of silver nanoparticles (AgNPs) using the Streptomyces tuirus S16 strain, presenting an eco-friendly alternative to mitigate the environmental and health risks of chemical synthesis methods. It focuses on optimizing medium culture conditions, understanding their physicochemical properties, and investigating their potential photothermal-based antibacterial application. The S16 strain was selected from soils contaminated with heavy metals to exploit its ability to produce diverse bioactive compounds. By employing the combination of Response Surface Methodology (RSM) and Artificial Neural Network (ANN)-Genetic Algorithm (GA) strategies, we optimized AgNPs synthesis, achieving an improvement of nearly 2.45 times the initial yield under specific conditions (Bennet's medium supplemented with glycerol [5 g/L] and casamino-acid [3 g/L] at 30 °C for 72 h). A detailed physicochemical characterization was conducted. Notably, the AgNPs were well dispersed, and a carbonaceous coating layer on their surface was confirmed using energy-dispersive X-ray spectroscopy. Furthermore, functional groups were identified using Fourier-transform infrared spectroscopy, which helped enhance the AgNPs' stability and biocompatibility. AgNPs also demonstrated efficient photothermal conversion under light irradiation (0.2 W/cm2), with temperatures increasing to 41.7 °C, after 30 min. In addition, treatment with light irradiation of E. coli K-12 model effectively reduced the concentration of AgNPs from 105 to 52.5 µg/mL, thereby enhancing the efficacy of silver nanoparticles in contact with the E. coli K-12. [ABSTRACT FROM AUTHOR]

Amid escalating antibiotic resistance, the urgency to combat multidrug-resistant (MDR) pathogens calls for innovative solutions. This study explores the potential of silver nanoparticles (AgNPs) synthesized from Vitex grandifolia leaves, chosen due to its affordability, accessibility, and therapeutic efficacy. The synthesis involves blending leaf extract with water and silver nitrate (AgNO3). Sunlight exposure led to the biological reduction of AgNO3, resulting in the formation of AgNPs characterized by a distinctive brown hue. These synthesized AgNPs underwent comprehensive characterization using various techniques including ultraviolet-visible spectroscopy (UV Vis), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). Antibacterial evaluation against multidrug-resistant (MDR) pathogens was conducted using the agar well diffusion method. Characterization studies confirmed the successful synthesis of AgNPs, with UV-visible spectroscopy revealing an absorbance peak at 350 nm. SEM analysis indicated an average particle size of approximately 13.12 nm, predominantly in rod-like shapes. EDX analysis corroborated the presence of silver, oxygen, and carbon, while XRD analysis unveiled a face-centred cubic crystalline structure. FTIR analysis identified various functional groups attributed to phytochemicals in the plant extract, acting as capping and reducing agents. Notably, the AgNPs exhibited a considerable band gap value (3.09 eV). For the antibacterial activity, AgNPs demonstrated significant efficacy against several multidrug-resistant pathogens, exhibiting a zone of inhibition of 15 mm. In summary, this study presents a rapid green synthesis method for AgNPs utilizing Vitex grandifolia leaves. The characterized AgNPs show promise in combating MDR pathogens, offering a sustainable and cost-effective solution in nanotechnology. [ABSTRACT FROM AUTHOR]

Dental caries is a multifactorial chronic dental disease impacting individuals across various ages. Several studies have shown that cariogenic bacteria primarily cause this disease in the oral cavity, notably Streptococcus mutans. Thus, this study aimed to characterize and develop toothpaste formulations by incorporating nano-hydroxyapatite (nHA) and silver nanoparticles (AgNPs) as active agents. The physicochemical properties of different formulations (F0-F5) were assessed, including odour, colour, taste, texture, consistency, homogeneity, pH, spreadability, and foaming ability. The antibacterial activity of the products obtained against Streptococcus mutans was tested using varying nHA concentrations (0.75, 1, and 1.25%). The results showed that the toothpaste formulation containing 1% nHA showed the most significant inhibitory effect, leading to an inhibition zone of 15.58 mm in diameter. Based on these findings, toothpaste containing nHA and AgNPs as active constituents was safe and efficacious in preventing dental caries. [ABSTRACT FROM AUTHOR]

In(III) tetraarylporphyrin complexes with 4‐thiomethylphenyl (1‐InPor), thien‐3‐yl (2‐InPor), thien‐2‐yl (3‐InPor) and 5‐bromothien‐2‐yl (4‐InPor) meso‐aryl rings have been synthesized and characterized. The complexes have been conjugated to gold and silver nanoparticles (AuNPs and AgNPs). The photodynamic antimicrobial chemotherapy (PACT) activities of 1–4‐InPor and their AuNP and AgNP conjugates have been investigated against both planktonic bacteria and biofilms of Gram‐(+) S. aureus and Gram‐(−) E. coli. 2.5 μg.mL−1 solutions of 1–4‐InPor exhibited favorable PACT activities against planktonic S. aureus with high Log10 reduction values in the 4.28–7.69 range upon 75 min photoirradiation with a Thorlabs M625L3 LED (240 mW.cm−2) mounted onto the illumination chamber of a Modulight 7710 medical laser system to provide a dose at the well‐plate of 86 mJ.cm−2.min−1. In contrast, low values in the 1.4–1.9 range were obtained against E. coli with 10 μg.mL−1 solutions. 1–4‐InPor exhibited relatively low PACT activity against the biofilm cells of S. aureus and E. coli. Conjugation of 1–4‐InPor to AgNPs and AuNPs significantly enhanced the PACT activities. This is demonstrated by the complete eradication of planktonic S. aureus at shorter irradiation times with high Log10 values>7.69 and moderate Log10 values>2 against planktonic E. coli for the meso‐thienylporphyrin conjugates. [ABSTRACT FROM AUTHOR]

Ultra-small Ag nanoparticles (<5 nm) loaded on a kaolinite surface were successfully prepared in large batches by a dry-process, displaying excellent broad-spectrum antimicrobial ability and size-dependent activity. This Ag-loaded kaolinite (Ag@AT/K) inhibited the growth of pathogenic bacteria and accelerated wound healing in in vivo experiments on MRSA-infected wounds. This work provides a new strategy for the preparation of mineral-based nanoscale antibacterial materials. [ABSTRACT FROM AUTHOR]

TiO2 is a widely used photocatalytic antibacterial material and shows good antibacterial properties under ultraviolet light. However, its antibacterial efficacy under visible light still remains limited. To develop low‐cost and biocompatible antibacterial materials, this article provides a facile method for in situ preparation of a trace amount of silver (Ag) doped TiO2 nanorods (TiO2NR–Ag) composites, which cannot only enhance the antibacterial properties under visible light, but also has good biocompatibility. Two representative epidemic strains, Staphylococcus aureus and Escherichia coli, are selected for analysis of the antibacterial properties of the obtained TiO2NR–Ag composite nanoparticles. The results demonstrate that even if the Ag doping level is as low as 2.5 × 10−4 wt% (i.e., Ag/TiO2 = 2.50 µg g−1), the TiO2NR–Ag composite nanoparticle coatings are transparent and exhibit exceptional antibacterial properties, which is attributed to synergistic enhanced bactericidal effect of the active substances generated by TiO2NR–Ag under visible light. The cytotoxicity and hemolysis rate results indicate that TiO2NR–Ag composite exhibit excellent biocompatibility. This study effectively improves the antibacterial effect of TiO2 photocatalytic nanomaterials while maintaining their biocompatibility, and the prepared TiO2NR–Ag composite nanoparticles can be applied in various fields such as window glasses, medical device surfaces, furniture surfaces, and optical devices, etc. [ABSTRACT FROM AUTHOR]

The synthesis of multifunctional composites still relies on the use of conventional methods. However, these methods are expensive, time consuming and require high volumes of reducing agents which are often toxic. In this study, composites of bentonite-supported silver nanoparticles were prepared comparatively by the conventional heating method and the rapid microwave method; and their antibacterial activity was investigated against Escherichia coli and Staphylococcus aureus. The crystalline nature of the composites was evaluated by X-ray diffraction (XRD), while transmission electron microscope (TEM) coupled with energy-dispersive spectroscope was used for morphology and elemental analysis, respectively. Surface area and pore size analysis of the composites were conducted by the Brunauer, Emmett and Teller analyzer. TEM images revealed successful synthesis of the composites with a better dispersion of the nanoparticles achieved through microwave, where nanoparticle sizes were 6–38 nm and 9–56 nm by the conventional method. It is worth noting that the composites were prepared in less than 30 min using microwave as compared to 2 h of the conventional method. The XRD spectra confirmed the formation of silver and not any other impurities of the metal. These results revealed that, although the two methods are comparable, microwave method is efficient and time saving and can, therefore, synthesize composites with well-dispersed and narrow distributed nanoparticles. The antibacterial results demonstrated that the prepared composites are effective in the inactivation of various bacteria. These composites could be applied in water treatment, wound dressing, packaging, etc. [ABSTRACT FROM AUTHOR]

In this study, zinc stannate (ZTO) was synthesized using the hydrothermal method at a temperature of 200 °C for duration of 20 h. The ZTO nanoparticles were prepared with varying concentrations of cobalt (Co) dopants (1%, 3%, and 5%) as well as co-doped with 3% cobalt and 3% iron (Co/Fe). The synthesized samples were then subjected to characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), zeta potential measurements, ultraviolet–visible (UV–Vis) spectroscopy, and Fourier-transform infrared spectroscopy (FTIR). The XRD analysis confirmed the presence of a spinel cubic structure in all the nanoparticles. It was observed that the crystallite size of the prepared samples decreased with increasing concentration of Co dopants. SEM analysis revealed the formation of spherical aggregates in a network-like structure. The transmittance spectra were recorded in the wavelength range of 200–1200 nm. The optical bandgap energy of the nanoparticles increased with higher Co doping concentrations. Specifically, the optical bandgap energies were found to be 3.8, 3.88, 3.9, 3.95, and 3.54 eV for pure ZTO, 1%Co doped ZTO, 3%Co doped ZTO, 5%Co doped ZTO, and 3%Co/3%Fe co-doped ZTO, respectively. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests demonstrated that ZTO nanoparticles doped with 6.25% Co/Fe were more effective against E. coli and S. aureus compared to other samples. The antibacterial efficacy of ZTO nanoparticles against S. aureus and E. coli was assessed using the zone of inhibition method. The results indicated that ZTO nanoparticles at three different concentrations showed significantly higher antibacterial activity against Gram-positive bacteria than against Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Increasing the antibacterial resistance of microorganisms stimulates the search for new antibacterial drugs. One of the significant advantages of using silver-containing drugs in the treatment of patients is a limited number of side effects when applied topically. In this scientific work, the sanitary and hygienic properties of the dressing material modified with silver nanoparticles were studied. The work used strains of gram-negative microbes (Moraxella spp., Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumonia, Acinetobacter baumannii, Salmonella enteritidis), gram-positive microbes (Staphylococcus haemoliticus, Staphylococcus aureus) and fungi of the genus Candida (Candida spp.). The reaction of the strains was analyzed by these microorganisms on the main antibiotics widely used in clinical practice in Russia. During the work, it was found that the dressing material modified with silver nanoparticles has high antimicrobial and antifungal activity. In addition, it was found that the effect of silver nanoparticles does not directly depend on the level of sensitivity of the microorganism to antibiotics. [ABSTRACT FROM AUTHOR]

The emergence of the global problem of multi-drug resistant bacteria (MDR) is closely related to the improper use of antibiotics, which gives birth to an urgent need for antimicrobial innovation in the medical and health field. Silver nanoparticles (AgNPs) show significant antibacterial potential because of their unique physical and chemical properties. By accurately regulating the morphology, size and surface properties of AgNPs, the antibacterial properties of AgNPs can be effectively enhanced and become a next generation antibacterial material with great development potential.The detection of the inhibitory effect of AgNPs on MDR provides more possibilities for the research and development of new antimicrobial agents.Promote the formation of AgNPs by redox reaction; determine the minimum inhibitory concentration (MIC) of AgNPs to bacteria by broth microdilution method; evaluate the killing efficacy of AgNPs against multi-drug-resistant bacteria by plate counting; evaluate the inhibitory effect of AgNPs on biofilm construction by crystal violet staining; study the drug resistance of bacteria by gradually increasing the concentration of AgNPs; and detect the toxicity of AgNPs to cells by CCK-8 method.AgNPs has a significant bactericidal effect on a variety of drug-resistant bacteria. After exposure to AgNPs solution for 12 hours, the number of E. coli decreased sharply, and S. aureus was basically eliminated after 16 hours. In particular, AgNPs showed stronger inhibition against Gram-negative bacteria. In addition, AgNPs can effectively hinder the formation of bacterial biofilm, and its inhibitory effect increases with the increase of AgNPs solution concentration. When AgNPs is used for a long time, the development of bacterial resistance to it is slow. From the point of view of safety, AgNPs has no harmful effects on organisms and has biosafety.AgNPs can inhibit MDR, and the bacteriostatic ability of Gram-negative bacteria is higher than that of Gram-positive bacteria. It can also inhibit the formation of bacterial biofilm, avoid drug resistance and reduce cytotoxicity. [ABSTRACT FROM AUTHOR]

Background: Motor and intellectual disabilities (MIDs) represent a great challenge for maintaining general health due to physical and cognitive limitations, particularly in the maintenance and preservation of oral health. Silver nanoparticles (AgNPs) have emerged as a promising therapeutic tool for bacterial control, including oral biofilms; however, knowledge of the bactericidal effectiveness of oral biofilms from patients with MIDs is insufficient. This study aims to determine the antimicrobial effect of AgNPs on different oral biofilms taken from patients with and without MIDs. Methods: Two sizes of AgNPs were prepared and characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Through consecutive sampling, biofilm samples were collected from 17 subjects with MIDs and 20 subjects without disorders. The antimicrobial effect was determined by obtaining the minimum inhibitory concentration (MIC) of AgNPs, and the identification and distribution of oral bacterial species were determined by polymerase chain reaction (PCR). Finally, correlations between sociodemographic characteristics and the antimicrobial levels of AgNPs were also explored. The values of the MIC results were analyzed with IBM-SPSS software (version25) using non-parametric tests for independent groups and correlations, with statistical significance being considered as p < 0.05. Results: Both sizes of AgNPs exhibited tight particle size distributions (smaller: 10.2 ± 0.7 nm; larger: 29.3 ± 2.3 nm) with zeta potential values (−35.0 ± 3.3 and −52.6 ± 8.5 mV, respectively) confirming the stability that resulted in little to no agglomeration of nanoparticles. Although both sizes of AgNPs had good antimicrobial activity in all oral biofilms, the smallest particles had the best antimicrobial effects on the oral biofilm samples from patients with and without MIDs, even better than chlorhexidine (CHX) (p < 0.05). Likewise, the patients with disabilities showed higher levels of antimicrobial sensitivity to AgNPs compared with CHX (p < 0.05). Although the microorganisms included in the biofilms of females had a statistically higher growth level, the AgNP antimicrobial effect was statistically similar in both genders (p > 0.05). The most frequent bacteria for all oral biofilms were S. mutans (100%), P. intermedia (91.6%), T. forsythia (75.0%), T. denticola (75.0%), P. gingivalis (66.6%), F. nucleatum (66.6%), S. sobrinus (50.0%), and A. actinomycetemcomitans (8.3%). Conclusions: AgNPs exhibited considerable antimicrobial potential to be used as a complementary and alternative tool in maintaining and preserving oral health in patients with MIDs. [ABSTRACT FROM AUTHOR]

Abstract The beekeeping industry plays a crucial role in local economies, contributing significantly to their growth. However, bee colonies often face the threat of American foulbrood (AFB), a dangerous disease caused by the Gram-positive bacterium Paenibacillus larvae (P. l.). While the antibiotic Tylosin has been suggested as a treatment, its bacterial resistance necessitates the search for more effective alternatives. This investigation focused on evaluating the potential of bee venom (BV) and silver nanoparticles (Ag NPs) as antibacterial agents against AFB. In vitro treatments were conducted using isolated AFB bacterial samples, with various concentrations of BV and Ag NPs (average size: 25nm) applied individually and in combination. The treatments were administered under both light and dark conditions. The viability of the treatments was assessed by monitoring the lifespans of treated bees and evaluating the treatment's efficiency within bee populations. Promising results were obtained with the use of Ag NPs, which effectively inhibited the progression of AFB. Moreover, the combination of BV and Ag NPs, known as bee venom/silver nanocomposites (BV/Ag NCs), significantly extended the natural lifespan of bees from 27 to 40 days. Notably, oral administration of BV in varying concentrations (1.53, 3.12, and 6.25 mg/mL) through sugary syrup doubled the bees' lifespan compared to the control group. The study established a significant correlation between the concentration of each treatment and the extent of bacterial inhibition. BV/Ag NCs demonstrated 1.4 times greater bactericidal efficiency under photo-stimulation with visible light compared to darkness, suggesting that light exposure enhances the effectiveness of BV/Ag NCs. The combination of BV and Ag NPs demonstrated enhanced antibacterial efficacy and prolonged honeybee lifespan. These results offer insights that can contribute to the development of safer and more efficient antibacterial agents for maintaining honeybee health.

The present study focused on evaluating the antibacterial properties, radical scavenging, and photocatalytic activities of Centaurea behen-mediated silver nanoparticles (Cb-AgNPs). The formation of Cb-AgNPs was approved by UV–Vis spectrometry, Fourier-transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy (SEM), energy dispersive X-ray and X-ray diffraction. The results showed that the obtained AgNPs have a maximum absorbance peak at 450 nm with spherical morphology and an average size of 13.03 ± 5.8 nm. The catalytic activity of the Cb-AgNPs was investigated using Safranin O (SO) solution as a cationic dye model. The Cb-AgNPs performed well in the removal of SO. The coupled physical adsorption/photocatalysis reaction calculated about 68% and 98% degradation of SO dye under solar irradiation. The Cb-AgNPs inhibited the growth of gram-negative or positive bacteria strains and had excellent DPPH radicals scavenging ability (100% in a concentration of 200 µg/ml) as well as a good effect on reducing coagulation time (at concentrations of 200 and 500 µg/mL reduced clotting time up to 3 min). Considering the fact that green synthesized Cb-AgNPs have antioxidant and antibacterial properties and have a good ability to reduce coagulation time, they can be used in wound dressings. As well as these NPs with good photocatalytic activity can be a suitable option for degrading organic pollutants. [ABSTRACT FROM AUTHOR]

The integration of two-dimensional Ti3C2Tx nanosheets and other materials offers broader application options in the antibacterial field. Ti3C2Tx-based composites demonstrate synergistic physical, chemical, and photodynamic antibacterial activity. In this review, we aim to explore the potential of Ti3C2Tx-based composites in the fabrication of an antibiotic-free antibacterial agent with a focus on their systematic classification, manufacturing technology, and application potential. We investigate various components of Ti3C2Tx-based composites, such as metals, metal oxides, metal sulfides, organic frameworks, photosensitizers, etc. We also summarize the fabrication techniques used for preparing Ti3C2Tx-based composites, including solution mixing, chemical synthesis, layer-by-layer self-assembly, electrostatic assembly, and three-dimensional (3D) printing. The most recent developments in antibacterial application are also thoroughly discussed, with special attention to the medical, water treatment, food preservation, flexible textile, and industrial sectors. Ultimately, the future directions and opportunities are delineated, underscoring the focus of further research, such as elucidating microscopic mechanisms, achieving a balance between biocompatibility and antibacterial efficiency, and investigating effective, eco-friendly synthesis techniques combined with intelligent technology. A survey of the literature provides a comprehensive overview of the state-of-the-art developments in Ti3C2Tx-based composites and their potential applications in various fields. This comprehensive review covers the variety, preparation methods, and applications of Ti3C2Tx-based composites, drawing upon a total of 171 English-language references. Notably, 155 of these references are from the past five years, indicating significant recent progress and interest in this research area. [ABSTRACT FROM AUTHOR]

A highly efficient, novel, two‐phase liquid method using phase transfer catalyst is reported to prepare β‐lactam‐conjugated silver nanoparticles as an approach to improve antibacterial activity of β‐lactams. In the method assisted by cetyltrimethylammonium bromide, NaBH4 reduced AgNO3 producing silver NPs that are coated with β‐lactams. The studies conducted provide a generalized method applicable to all types of β‐lactam substrates for capping on silver NPs. The NPs have been characterized by UV–Visible, Fourier transform infrared spectroscopy, x‐ray diffraction, transmission electron microscopy, and dynamic light scattering methods. [ABSTRACT FROM AUTHOR]

Today, the production and use of materials with nanometer diversity is increasing day by day due to the unique and fascinating features of these materials. Until now, various physical and chemical methods have been used for the synthesis of silver nanoparticles (AgNPs), but the use of plants for the synthesis of AgNPs is very fast, simple, non-toxic, and environmentally friendly. In this research, the aqueous extract (AE) of Capparis plants was used for the biosynthesis of AgNPs. The color of the silver nitrate solution changed to reddish color after adding the extract. The Antimicrobial activity of AgNPs against Streptococcus pyogenes, Streptococcus pneumoniae, S. saprophyticus, Hafnia alvei, Acinetobacter. baumannii, Enterococcus faecalis, Proteus mirabilis, Serratia marcescens, Staphylococcus aureus bacteria were investigated by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using microdilution method. The amount of total phenol and flavonoids in the methanolic extract (ME) of capparis leaves was equal to 229.9-28.09 mg per gram of dry matter. The antioxidant properties of the ME of capparis were 85.18%. The greatest effect of the ME of the medicinal plant capparis was 0.2315 on the inactivity of E. coli and the greatest effect of green AgNPs synthesized from the AE of the medicinal plant Capparis with ELISA of 0.3740 was on the inactivity of S. mutanis. The maximum diameter of the inhibitor zone (MDIZ) was 5.5 mm due to the inactivity of H. alvi bacteria. The results of this research showed that the leaf extract of the Capparis spinosa f. inermis Knocheplant is capable of synthesizing AgNPs and the synthetic nanoparticles showed good antimicrobial activity against pathogenic strains in vitro. [ABSTRACT FROM AUTHOR]

A polydopamine polyelectrolyte hydrogel was developed by ionic crosslinking dextran sulfate with a copolymer of polyethyleneimine and polydopamine. Gelation was promoted by the slow hydrolysis of glucono-δ-lactone. Within this hydrogel, silver nanoparticles were generated in situ, ranging from 25 nm to 200 nm in size. The antibacterial activity of the hydrogel was proportional to the quantity of silver nanoparticles produced, increasing as the nanoparticle count rose. The hydrogels demonstrated broad-spectrum antibacterial efficacy at concentrations up to 108 cells/mL for P. aeruginosa, K. pneumoniae, E. coli and S. aureus, the four most prevalent bacterial pathogens in chronic septic wounds. In ex vivo studies on human skin, biocompatibility was enhanced by the presence of polydopamine. Dextran sulfate is a known irritant, but formulations with polydopamine showed improved cell viability and reduced levels of the inflammatory biomarkers IL-8 and IL-1α. Silver nanoparticles can inhibit cell migration, but an ex vivo human skin study showed significant re-epithelialization in wounds treated with hydrogels containing silver nanoparticles. [ABSTRACT FROM AUTHOR]

The use of plants in the biological production of silver nanoparticles for antibacterial applications is a growing field of research. In the current work, we formulated Ocimum kilimandscharicum extracts using silver nanoparticles, and evaluated its potential antibacterial activity. Aqueous and methanol plant extracts were used to reduce silver nitrate at different time intervals (30 to 150 minutes) and pH (2 to 11). The UV-visible absorption spectrum recorded for methanol and aqueous extracts revealed a successful synthesis of AgNPs for methanol and aqueous extracts. The antimicrobial activity of the AgNPs was evaluated against Escherichia coli ATCC 25922, Salmonella choleraesuius ATCC 10708, and Staphylococcus aureus ATCC 25923 The best inhibition zone for the methanol and aqueous-mediated AgNPs, ranging from 12 ± 1 to 16 ± 1mm. Additionally, the methanol and aqueous extract silver nanoparticles had the same Minimum Inhibitory Concentration (6.25 ± 0.00 mg/ml), whereas the Minimum Bactericidal Concentrations were 12.5 ± 0.00 and 25 ± 0.00 mg/ml, respectively. The highest inhibition zone of 16 ± 1 mm was observed against Salmonella choleraesuius with 50 ± 0.00 mg/ml aqueous silver nanoparticles. The results show that the silver nanoparticles made with Ocimum kilimandscharicum have antibacterial action against those microorganisms. [ABSTRACT FROM AUTHOR]

Metal and metal oxide nanostructured materials have been chemically and physically characterized and tested concerning methylene blue (MB) photoremoval and UV antibacterial activity against Escherichia coli and Staphylococcus aureus. In detail, silver nanoparticles and commercial BaTiO3 nanoparticles were modified to obtain nanocomposites through sonicated sol–gel TiO2 synthesis and the photodeposition of Ag nanoparticles, respectively. The characterization results of pristine nanomaterials and synthetized photocatalysts revealed significant differences in specific surface area (SSA), the presence of impurities in commercial Ag nanoparticles, an anatase phase with brookite traces for TiO2-based nanomaterials, and a mixed cubic–tetragonal phase for BaTiO3. Silver nanoparticles exhibited superior antibacterial activity at different dosages; however, they were inactive in the photoremoval of the dye. The silver–TiOx nanocomposite demonstrated an activity in the UV photodegradation of MB and UV inhibition of bacterial growth. Specifically, TiO2/AgNP (30–50 nm) reduced growth by 487.5 and 1.1 × 103 times for Escherichia coli and Staphylococcus aureus, respectively, at a dose of 500 μg/mL under UV irradiation. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a safe, flexible and biocompatible polymer that is suitable as a delivery mechanism for Moringa oleifera leaf extract and silver nanoparticles which have antibacterial and wound healing properties. In this study, BC impregnated with Moringa oleifera leaf extract and/or silver nanoparticles was characterized using the Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD) and field emission scanning electron microscopy with energy dispersive X-ray spectroscopy and mapping (FESEM-EDX-Mapping). The antibacterial activity of the impregnated BC was also evaluated using disc diffusion method. Based on the obtained results, impregnation of Moringa oleifera leaf extract and silver nanoparticles apparently improved crystallinity of BC. The presence of both formulants in BC could also be detected through FTIR and FESEM-EDX-Mapping. The antibacterial activity of Moringa oleifera and silver nanoparticles impregnated BC against gram-positive and gram-negative bacteria, however, varies depending on its formulation. Briefly, the impregnated BC has potential to be applied as antibacterial dressing, but more intensive studies need to be conducted in future to confirm its effectiveness and safety. [ABSTRACT FROM AUTHOR]

In the present study, green synthesis of silver nanoparticles (VNE-AgNPs) via Verbascum nudatum extract was carried out for the first time. The synthesized AgNPs were characterized by different spectral methods such as UV–vis, FTIR, XRD, TEM, and EDAX. According to TEM analyses, the average size range of AgNPs was 17–21 nm, and the dominant peaks in the 111°, 200°, 221°, and 311° planes in the XRD pattern indicated the Ag-NPs FCC crystal structure. FTIR data showed that VNE-AgNPs interacted with many reducing, capping, and stabilizing phytochemicals during green synthesis. VNE-AgNPs had higher antibacterial activity against S. aureus and E. coli bacterial strains with a maximum inhibition zone of 21 and 18 mm, respectively, than penicillin 5 IU, used as a positive control in the study. The cytotoxic effect of VNE-AgNPs appeared at a concentration of 50 µg/mL in L929 cells and 5 µg/mL in cancer (A549) cells. When the impact of VNE-AgNPs and C-AgNPs on inflammation was compared, it was found that VNE-AgNPs increased TNF-α levels (333.45 ± 67.20 ng/mg-protein) statistically (p < 0.05) more than TNF-α levels (256.92 ± 27.88 ng/mg-protein) in cells treated with C-AgNPs. VNE-Ag-NPs were found to have a degradation efficiency of 65% against methylene blue (MB) dye within 3 h. [ABSTRACT FROM AUTHOR]

Bacterial infection is a thorny problem, and it is of great significance to developing green and efficient biological antibacterial agents that can replace antibiotics. This study aimed to rapidly prepare a new type of green antibacterial nanoemulsion containing silver nanoparticles in one step by using Blumea balsamifera oil (BBO) as an oil phase and tea saponin (TS) as a natural emulsifier and reducing agent. The optimum preparation conditions of the AgNPs@BBO-TS NE were determined, as well as its physicochemical properties and antibacterial activity in vitro being investigated. The results showed that the average particle size of the AgNPs@BBO-TS NE was 249.47 ± 6.23 nm, the PDI was 0.239 ± 0.003, and the zeta potential was −35.82 ± 4.26 mV. The produced AgNPs@BBO-TS NE showed good stability after centrifugation and 30-day storage. Moreover, the AgNPs@BBO-TS NE had an excellent antimicrobial effect on Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. These results demonstrated that the AgNPs@BBO-TS NE produced in this study can be used as an efficient and green antibacterial agent in the biomedical field. [ABSTRACT FROM AUTHOR]

Infections related to biomedical devices and materials remain a critical healthcare concern, leading to considerable morbidity and disease burden. To combat this issue, the development of fibers with inherent antibacterial properties has garnered significant interest. These fibers offer a large surface area, making them ideal candidates for effective treatment with antibacterial agents. In this study, we present a straightforward procedure for applying silver nanoparticles (AgNPs) to hydrophobic polylactic acid (PLA) fibers that have been surface-modified using sodium hydroxide (NaOH). The method involved electrospinning to create a high-thickness web of PLA fibers, followed by gradual surface modification with NaOH at two different concentrations (0.5 M and 1 M). To confer antibacterial properties to the modified surface samples, we applied silver nanoparticles (AgNPs) at a concentration of 25 mM. In contrast to regular PLA fibers, the surfaces of hydrolyzed PLA (PLA-H) fibers, AgNPs-treated PLA (PLA-A), and hydrolyzed-AgNPs coated PLA (PLA-H-A) fibers exhibited a non-uniform and highly porous structure. EDX analysis provided crucial information about the presence and integration of Ag nanoparticles into the PLA fibers. The PLA-H-A sample exhibited the highest hydrophilicity, with a contact angle of 65.7°. Additionally, the results from differential scanning calorimetry indicated an increase in PLA-H-A's glass transition temperature. Notably, in the Gram-positive Escherichia coli (E. coli) and Gram-negative Staphylococcus aureus (S. aureus) tests, the PLA-H-A samples demonstrated highly effective antibacterial properties, effectively preventing bacterial growth. [ABSTRACT FROM AUTHOR]

Several technologies are employed for the synthesis of silver nanoparticles, each synthesis technique has advantages and disadvantages, and the best technique relies on the application at hand, the required qualities of the nanoparticles, and the size of the product. But in this article green synthesis were followed. In this research, AgNPs were synthesized using Salvia Sclarea leaf extract in green synthetic routes. The synthesized nanoparticles were examined using UV–vis spectroscopy, powder XRD, SEM, and FT-IR. Here three different type of silver nanoparticles were biosynthesized, AgNPs-1, AgNPs-2, and AgNPs-3 (where composition of AgNO3 and extract were 6:1, 10:1 and 14:1 respectively). The catalytic ability of AgNPs 1–3 was determine in the reduction of nitro-compounds into corresponding amines, where AgNPs-2 was found efficient reductive catalyst. Moreover, antibacterial activities were checked against both gram-positive (Bacillus Suntilis) and gram-negative bacteria (Klebsiella pneumoniae). Upon increasing Ag contents antibacterial activities were found in increasing mode. Which open new era of knowledge for further consideration. [ABSTRACT FROM AUTHOR]

The plant mediated synthesis of metallic nanoparticles is a fast-growing area of interest in the field of nanotechnology due to its eco-friendly approach. This study demonstrated the green synthesis of silver nanoparticles (AgNPs) using Tagetes minuta leaf extract. The AgNPs were characterised using UV-visible spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis and Fourier transform infrared (FTIR) spectroscopy. UV-visible spectrum of synthesised silver nanoparticles showed maximum peak at 442 nm. TEM revealed that the particles were spherical in shape and size ranging from 10 to 50 nm. The EDX spectrum confirmed the presence of silver metal. Preliminary antibacterial activity was determined using the agar well diffusion method, which showed growth inhibition against selected gram-positive and gram-negative bacteria. [ABSTRACT FROM AUTHOR]

This study investigates Guiera senegalensis J.F. Gmel (Combretaceae), a widely acknowledged herb in Africa for its medicinal properties against various ailments, including fever, diarrhea, diabetes, dysentery, eczema, malaria, cough, tuberculosis, and its potential to enhance milk production in lactating women. The research focuses on utilizing Guiera senegalensis for synthesizing silver nano-particles (GS-AgNPs), due to its abundance in primary and secondary metabolites. The primary aim is to produce GS-AgNPs and assess their antibacterial efficacy. The synthesis of GS-AgNPs involved mixing a silver salt solution with the water leaf-extract. Characterization of the nanoparticles was conducted using Ultraviolet-visible spectroscopy with surface-plasmon-resonance (S-P-R) analysis at 390 nanometers (nm). Fourier transform infrared spectroscopy (F-T-IR) investigated the identity of the phytochemicals responsible for the green reduction of silver ions. X-ray diffraction (X-RD) confirmed the face-centered-cubic crystallinity of the GS-AgNPs with a mean size (33 nm). The antibacterial potential of GS-AgNPs was evaluated against both gram-negative (Escherichia coli and Salmonella typhi) and gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) using the Agar-well method. Results demonstrated the inhibitory effect of GS-AgNPs on microbial growth, with zone-of-inhibition (ZOI) ranging from 4-7 millimeters (mm) to 16-19 mm at concentrations of 10 mg/cm³ and 20 mg/cm³, respectively. In comparison, the aqueous leaf extract exhibited Z-OI between 1.3-6 mm. GS-AgNPs displayed superior antibacterial activity against both Gram-positive and Gramnegative bacteria when compared to the aqueous leaf extract. [ABSTRACT FROM AUTHOR]

This study defined a facile, inexpensive, and benign method to fabricate silver nanoparticles (AgNPs) using Tradescantia pallidum var. purpurea aqueous leaves extract for the first time. A UV–vis spectrum showed that the evaluated extract was promising for green synthesis of the SNP, with the highest peak of absorption between 450 and 550 nm. The phytochemicals present in the plant extract acts as capping and stabilization agent were confirmed by FTIR analysis. EDX proved the presence of Ag while SEM confirmed the AgNPs with the spherical shape. TEM revealed the average particle size was 23 nm. Additionally, AgNPs exhibited significant antibacterial activity and turbidimetry analysis showed MIC and MBC was in range of 25–100 µg/mL against both Gram positive and Gram-negative bacteria in Luria Bertani broth cultures. The AgNPs exhibited potent antibacterial activity against gram-positive bacteria, with a ZOI of 12 ± 0.25 mm produced against BacillusB subtilis showed the largest zones of inhibition, which were greater than the positive control (cefotaxime). The MIC values were 50 µg/mL for Pseudomonas aeruginosa, 25 µg/mL for Staphylococcus aureus and Escherichia coli, and 100 µg/mL for B. subtilis, confirming their significant antibacterial action. AgNPs inhibited the DDPH free radical scavenging activity with an IC50 = 91.87 µg/mL. It is believed that these AgNPs play a crucial role in determining the therapeutic potential of T. pallida due to their biological efficacy. [ABSTRACT FROM AUTHOR]

Polymer-based sponges loaded with antibacterial agents are potential wound dressings ideal for treating bacteria-infected wounds. Gelatin/poly (ethylene glycol) (PEG) sponge-based wound dressings loaded with metronidazole and Ag nanoparticles with different degrees of cross-linking were prepared, and their capability to treat infected wounds in vitro was evaluated. The degree of cross-linking of the sponges varied, and the porosity of the sponges was in the range of 15.64–91.10%. The amount of gelatin used to prepare the sponges influenced the porosity of the sponges. The sponges displayed an initial burst drug release of metronidazole followed by a sustained release profile. The sponges exhibited considerable antibacterial activity against Gram-positive and Gram-negative bacteria. The % cell viability of the sponges was in the range of 71.17–86.10%, indicating distinguished biocompatibility. The in vitro experiment showed that the sponge loaded with metronidazole, SAM2%, displayed a significant reduction of 66.68% in the scratch area compared to the sponge loaded with a combination of silver nanoparticles and metronidazole with a closure rate of 46.61% at 96 h. The promising features of the sponges indicate that they are potential wound dressings for treating infected wounds. [ABSTRACT FROM AUTHOR]

Solanum trilobatum L. (Solanaceae), commonly known as nightshade, has been traditionally used by various populations to treat a variety of ailments. Environment-friendly alternatives to chemical and physical procedures for the synthesis of nanomaterials have been proposed. In this research, the hot plate combustion method is used to synthesize nickel oxide nanoparticles (AgNPs) from silver nitrate and S. trilobatum leaf extract. According to X-ray diffraction (XRD) tests, the cubic phase was face-centered, had good crystallinity, and had average crystallite sizes. According to morphological studies, the surface has a cylindrical and rod-like morphology, and average particle size estimates from UV-visible spectroscopy (UV), Fourier transform infrared (FT-IR), concur well with XRD, and the bio-reduced silver nanoparticles were characterized. Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, Pseudomonas aeruginosa, and the human pathogenic microorganisms were used to investigate the antibacterial efficacy (12.5, 25, 50 µg/mL) of these biologically created silver nanoparticles. [ABSTRACT FROM AUTHOR]

Aims To evaluate the effect of silver nanoparticles alone and in combination with Triclosan, and trans -cinnamaldehyde against Staphylococcus aureus and Escherichia coli biofilms on sutures to improve patients' outcomes. Methods and results Silver nanoparticles were prepared by chemical method and characterized by UV–visible spectrophotometer and dynamic light scattering. The minimum inhibitory concentration was assessed by the Microdilution assay. The antibiofilm activity was determined using crystal violet assay. A checkerboard assay using the fractional inhibitory concentration index and time-kill curve was used to investigate the synergistic effect of silver nanoparticle combinations. The hemolytic activity was determined using an erythrocyte hemolytic assay. Our results revealed that silver nanoparticles, Triclosan, and trans- cinnamaldehyde (TCA) inhibited S.aureus and E.coli biofilms. Silver nanoparticles with TCA showed a synergistic effect (FICI values 0.35 and 0.45 against S. aureus and E. coli biofilms, respectively), and silver nanoparticles with Triclosan showed complete inhibition of S. aureus biofilm. The hemolytic activity was <2.50% for the combinations. [ABSTRACT FROM AUTHOR]

Silver-based antibacterial coatings limit the spread of hospital-acquired infections. Indeed, the use of silver and silver oxide nanoparticles (Ag and AgO NPs) incorporated in amorphous hydrogenated carbon (a-C:H) as a matrix demonstrates a promising approach to reduce microbial contamination on environmental surfaces. However, its success as an antibacterial coating hinges on the control of Ag+ release. In this sense, if a continuous release is required, an additional barrier is needed to extend the release time of Ag+. Thus, this research investigated the use of a plasma fluoropolymer (CFx) as an additional top layer to elongate Ag+ release and increase the antibacterial activity due to its high hydrophobic nature. Herein, a porous CFx film was deposited on a-C:H containing Ag and AgO NPs using pulsed afterglow low pressure plasma polymerization. The chemical composition, surface wettability and morphology, release profile, and antibacterial activity were analyzed. Overall, the combination of a-C:H:Ag (12.1 at. % of Ag) and CFx film (120.0°, F/C = 0.8) successfully inactivated 88% of E. coli and delayed biofilm formation after 12 h. Thus, using a hybrid approach composed of Ag NPs and a hydrophobic polymeric layer, it was possible to increase the overall antibacterial activity of the coating. [ABSTRACT FROM AUTHOR]

A rapid, eco-friendly, and simple method for the synthesis of long-lasting (2 years) silver nanoparticles (AgNPs) is reported using aqueous leaf and petal extracts of Tagetes erecta L. The particles were characterized using UV-Visible spectrophotometry and the analytical and crystallographic techniques of transmission electron microscopy (TEM). The longevity of the AgNPs was studied using UV-Vis and high-resolution TEM. The antibacterial activity of the particles against Erwinia amylovora was evaluated using the Kirby–Bauer disk diffusion method. The results were analyzed using ANOVA and Tukey's test (p ≤ 0.05). Both the leaf and petal extracts produced AgNPs, but the leaf extract (1 mL) was long-lasting and quasi-spherical (17.64 ± 8.87 nm), with an absorbance of UV-Vis λmax 433 and a crystalline structure (fcc, 111). Phenols, flavonoids, tannins, and terpenoids which are associated with -OH, C=O, and C=C were identified in the extracts and could act as reducing and stabilizing agents. The best antibacterial activity was obtained with a nanoparticle concentration of 50 mg AgNPs L−1. The main contribution of the present research is to present a sustainable method for producing nanoparticles which are stable for 2 years and with antibacterial activity against E. amylovora, one of most threatening pathogens to pear and apple productions. [ABSTRACT FROM AUTHOR]

Our study aimed to evaluate the antibacterial activities and dentin bond strengths of silver nanoparticles (Ag NPs) and silver nano-graphene oxide nanocomposites (Ag@nGO NCs) produced by green and chemical synthesis methods added to the dental adhesive. Ag NPs were produced by green synthesis (biogenic) (B-Ag NPs) and chemical synthesis methods (C–Ag NPs) and deposited on nGO (nano-graphene oxide). Ag NPs and Ag@nGO NCs (0.05% w/w) were added to the primer and bond (Clearfil SE Bond). Group 1: control, Group 2: nGO, Group 3: B-Ag NPs, Group 4: B-Ag@nGO NCs, Group 5: C–Ag NPs, Group 6: C–Ag@nGO NCs. Streptococcus mutans (S. mutans) live/dead assay analysis, MTT metabolic activity test, agar disc diffusion test, lactic acid production, and colony forming units (CFUs) tests were performed. Bond strength values were determined by the microtensile bond strength test (μTBS). Failure types were determined by evaluating with SEM. Statistical analysis was performed using one-way ANOVA and two-way ANOVA (p < 0.05). There was a difference between the groups in the viable bacteria ratio and lactic acid production tests (p < 0.05). When the inhibition zone and S. mutans CFUs were evaluated, there was no difference between Group 3 and Group 4 (p > 0.05), but there was a difference between the other groups (p < 0.05). When the metabolic activity of S. mutans was evaluated, there was a difference between Group 1 and other groups, and between Group 2 and Group 5, and Group 6 (p < 0.05). There was no difference between the groups in the μTBS values (p > 0.05). As a result, although the antibacterial activity of B-Ag NPs and B-Ag@nGO Ag NPs obtained by green synthesis is lower than that of chemically synthesis obtained C–Ag NPs and C–Ag@nGO NCs, they provided higher antibacterial activity compared to the control group and did not reduce μTBS. The addition of biogenic Ag NPs to the adhesive system increased the antibacterial effect by maintaining the bond strength of the adhesive. Antibacterial adhesives can increase the restoration life by protecting the tooth-adhesive interface. [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]

Antibacterial hydrogels have attracted significant attention due to their diverse applications, efficient antimicrobial properties, and adaptability to various environments and requirements. However, their relatively fragile structure, coupled with the potential for environmental toxicity when exposed to their surroundings for extended periods, may significantly limit their practical application potential. In this work, a composite hydrogel was synthesized with outstanding mechanical features and antibacterial capability. The hydrogel was developed through the combination of the eco-friendly and enduring antibacterial agent, lignin silver nanoparticles (Lig-Ag NPs), with polyvinyl alcohol (PVA) and sodium alginate (SA), in varying proportions. The successful synthesis of the hydrogel and the dispersed distribution of Lig-Ag NPs within the hydrogel were confirmed by various analytical techniques, including field emission scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), mercury intrusion porosimetry (MIP), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The formation of multiple hydrogen bonds between Lig-Ag NPs and the composites contributed to a more stable and dense network structure of the hydrogel, consequently enhancing its mechanical properties. Rheological tests revealed that the hydrogel exhibited an elastic response and demonstrated outstanding self-recovery properties. Significantly, the antibacterial hydrogel demonstrated effectiveness against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), achieving a <5% survival of bacteria within 12 h. This study presented a green and straightforward synthetic strategy for the application of antibacterial composite hydrogels in various fields. [ABSTRACT FROM AUTHOR]

Silver nanoparticles have shown inhibitory capabilities and its use in battling viral infections are strengthened by its potent antibacterial activity. Notably, since it directly affects antiviral efficacy, the proper choice of synthesis process for making silver nanoparticles is a vital element to be taken into consideration. The synthesis of silver nanoparticles for the treatment of viral and bacterial infections involves creating silver particles at the nanoscale with unique antimicrobial properties. Various methods exist for synthesizing silver nanoparticles, including chemical reduction, green synthesis, and physical methods. Chemical reduction involves using reducing agents to convert silver ions into silver nanoparticles. Green synthesis employs reducing agents in an environmentally friendly manner. Physical methods rely on techniques such as laser ablation or thermal evaporation to produce silver nanoparticles. In order to provide technological guidance for choosing antiviral silver nanoparticle manufacturing methods, this paper introduces and explores alternative synthesis methods for creating silver nanoparticles. [ABSTRACT FROM AUTHOR]

This research explores the eco-friendly synthesis of silver nanoparticles (AgNPs) using Cassia occidentalis L. seed extract. Various analytical techniques, including UV–visible spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive X-ray spectroscopy (EDX), were employed for comprehensive characterization. The UV–visible spectra revealed a distinct peak at 425 nm, while the seed extract exhibited peaks at 220 and 248 nm, indicating the presence of polyphenols and phytochemicals. High-resolution TEM unveiled spherical and oval-shaped AgNPs with diameters ranging from 6.44 to 28.50 nm. The SEM exhibiting a spherical shape and a polydisperse nature, thus providing insights into the morphology of the AgNPs. EDX analysis confirmed the presence of silver atoms at 10.01% in the sample. XRD results unequivocally confirm the crystalline nature of the AgNPs suspension, thereby providing valuable insights into their structural characteristics and purity. The antioxidant properties of AgNPs, C. occidentalis seed extract, and butylated hydroxytoluene (BHT) were assessed, revealing IC50 values of 345, 500, and 434 μg/mL, respectively. Antibacterial evaluation against Bacillus subtilis, Staphylococcus aureus, and Escherichia coli demonstrated heightened sensitivity of bacteria to AgNPs compared to AgNO3. Standard antibiotics, tetracycline, and ciprofloxacin, acting as positive controls, exhibited substantial antibacterial efficacy. The green-synthesized AgNPs displayed potent antibacterial activity, suggesting their potential as a viable alternative to conventional antibiotics for combating pathogenic bacterial infections. Furthermore, potential biomedical applications of AgNPs were thoroughly discussed. [ABSTRACT FROM AUTHOR]

The synthesis of Cyanobacteria‐mediated nanoparticles has attracted great attention due to its ecofriendly, cost‐effective and biocompatible properties. Silver nanoparticles (AgNPs) are used in different areas such as medicine, household products, disinfectants or food storage. The present study aimed the biosynthesis of AgNPs from Cyanobacterial Chroococcus sp. and their antimicrobial activities on some important pathogen bacterial species. According to the obtained data, optimal conditions for synthesis of AgNPs were extract rate 3 : 1 v/v (cell extract/AgNO3), silver salt concentration 10 mM, pH 7, temperature 60 °C and time 30 minutes. The surface plasmon resonance peak of AgNPs was observed at 420–430 nm, and AgNPs were well‐dispersed spherical with an average size of 11–13 nm in diameter by TEM. SEM‐EDX analysis revealed a strong signal of silver. With FTIR analyzes, shift in the absorption bands after the AgNPs formation was confirmed. X‐ray diffraction analysis exhibited that the AgNPs were cubic crystalline shape. Zeta potential of AgNPs showed ‐ 20 mV. The AgNPs strong showed antibacterial activity on an opportunistic bacterial pathogens of Micococcus luteus, Bacillus subtilis and Pseudomonas aeroginosa. The effective and rapid synthesis of Chroococcus‐mediated AgNPs and their strong antimicrobial effects can create an important potential for their use in biomedical and environmental applications. [ABSTRACT FROM AUTHOR]

Indeed, considerable efforts have been made in the domain of silver nanoparticles, including the construction and wide‐ranging applications. This work involves the synthesis and characterization of salophen anchored silver nanoparticles (AgNPs), and its utilization for selective detection of Fe2+ and Cu2+ ions in DMSO. These AgNPs were synthesized by the reduction of Ag+ ions with salophen ligand, and were characterized by different techniques which include UV‐visible, fluorescence, FTIR, SEM, EDX, TEM, PXRD, DLS, and zeta potential. The negative zeta potential value of −19.6 mV evidenced the stability of the AgNPs. These AgNPs were found to sense Fe2+ and Cu2+ ions selectively in DMSO solution at various concentrations. Instant color change from olive to brown as well as olive to light olive was observed while detecting Fe2+ and Cu2+ ions by the nanoprobe, respectively. UV‐visible and fluorescence spectroscopic investigations were carried out to establish the sensing ability of the nanoprobe. Additionally, AgNPs revealed promising antibacterial activity selectively against gram‐negative bacteria over gram‐positive bacteria. Thus, our approach opens up a new track to design novel and operative functionalized nanomaterials for real‐life sensing and biomedical applications. [ABSTRACT FROM AUTHOR]

Antibacterial resistance among uro-pathogens has become a global issue for bacterial infection treatment. The antibacterial activity of various plant extracts and silver nanoparticles (AgNPs) derived from medicinal plant extract was evaluated against different drug-resistant uro-pathogens isolated from clinical patients by Agar Well Diffusion and Minimum Inhibitory Concentration (MIC) assays. A total of 100 urine samples were collected from patients admitted to the hospital followed by the identification of Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Proteus mirabilis, Enterobacter aerogenes, and Klebsiella pneumonia through colony morphology, gram staining, and biochemical characterization. All isolates were highly resistant to all the tested drugs except Amikacin, Gentamicin, and Imipenem. Organic extracts of clove have potent antibacterial activity against all drug-resistant isolates. Interestingly P. aeruginosa was sensitive to all inorganic extracts. These results revealed that the organic extracts of medicinal plants showed more consistent antimicrobial activity compared to their aqueous fraction. Furthermore, the green synthesis of AgNPs derived from clove extract showed strong activity against all tested pathogens followed by green synthesis of AgNPs derived from garlic, ginger, kalwonji, turmeric, and thymus extract respectively compared to medicinal plant extract. Moreover, MIC results showed that AgNPs derived from medicinal plant extract indicate higher efficiency in inhibiting bacterial growth than the medicinal plant extract. The current finding shows that AgNPs derived from plant extract can be recommended as a good alternative for treating the resistant uro-pathogens strains as compared to synthetic drugs and will be considered an attractive candidate for future biological applications. [ABSTRACT FROM AUTHOR]

OBJECTIVE To establish the lowest effective dose of commercially available nanoparticulate silver (AgNP) for antibacterial activity against Escherichia coli (E coli) and methicillin-resistant Staphylococcus pseudintermedius (MRSP), in vitro, and to establish the effect of incorporating AgNP into carriers for sustained release on this antibacterial activity. SAMPLES Silver nanoparticle dispersion (0.02 mg/mL) composed of citrate-stabilized, spherical, 10 nm diameter nanoparticles in aqueous buffer. PROCEDURES E coli and MRSP were treated with 0.01 mg/mL AgNP. The highest concentration of bacteria where growth was inhibited by AgNP was selected for treatment with 0.01 mg/mL AgNP incorporated 3 carriers for sustained release: calcium sulfate hemihydrate (CSH) beads, poloxamer 407 gel, and gelatin sponge, respectively. The antibacterial activity of AgNP and AgNP incorporated into carriers for sustained release was compared with a mixed linear effects model. RESULTS AgNP inhibited bacterial growth at a concentration of 101 for MRSP and 103 for E coli. For MRSP, the treatment group was associated with bacterial growth (P < .001) while the concentration of bacteria and time were not (P = .292 and P = .289, respectively). For E coli, the treatment group and concentration of bacteria were associated with bacterial growth (P < .001 and = .029, respectively) while time was not (P = .095). Poloxamer 407 gel exerted standalone antibacterial activity against both species of bacteria; sponge and CSH beads did not. CLINICAL RELEVANCE AgNP has antibacterial activity against E coli and MRSP, which can be reduced when incorporated into carriers for sustained release. Poloxamer 407 gel alone and combined with AgNP exerts antibacterial activity against E coli and MRSP. [ABSTRACT FROM AUTHOR]

Our aims in this work are the preparation of an ionic liquid based on heterocyclic compounds with Ag nanoparticles and the investigation of its application as an antibacterial and anticandidal agent. These goals were achieved through the fabrication of an ionic liquid based on Ag nanoparticles with 5-Amino-3-(4-fluorophenyl)-N-hexadecyl-7-(4-methylphenyl)-2-H spiro[cyclohexane1,2'-[1,3]thiazolo [4,5-b]pyridine]-6-carbonitrile (P16). The nanostructure of the prepared ionic liquid was characterized using techniques such as FTIR, 1HNMR, 13CNMR, UV, SEM, and TEM. The biological activity of the prepared compound (P16) and its nanocomposites with Ag nanoparticles was tested using five clinical bacteria (Pseudomonas aeruginosa 249; Escherichia coli 141; Enterobacter cloacae 235; Staphylococcus epidermidis BC 161, and methicillin-resistant S. aureus 217), and three Candida species (Candida utilis ATCC 9255; C. tropicalis ATCC 1362, and C. albicans ATCC 20402). The FTIR, 1HNMR, and 13CNMR results confirmed the chemical structure of the synthesized P16 compound. The nanostructure of the prepared ionic liquid was determined based on data obtained from the UV, SEM, and TEM tests. The antibacterial and anticandidal results showed that the biological activity of the compound (P16) was enhanced after the formation of nanocomposite structures with Ag nanoparticles. Moreover, the biological activity of the compound itself (P16) and that of its nanocomposite structure with Ag nanoparticles was higher than that of ampicillin and amphotericin B, which were used as control drugs in this work. [ABSTRACT FROM AUTHOR]

The current study explored the use of the ethanolic extract of Enteromorpha intestinalis to determine its capability to synthesize silver nanoparticles. The GC-mass technique was utilized to identify the active compounds in the algal ethanolic extract. The extract's potential in fabricating silver nanoparticles was tested, and their formation was inferred through the color change of the mixture from light green to dark brown. The synthesized nanoparticles were characterized using various techniques, (FTIR) spectroscopy, a scanning electron microscope (SEM), and an energy-dispersive X-ray spectroscopy (EDX). In addition, they were analyzed using X-ray diffraction (XRD). The antibacterial effectiveness was tested through the agar well diffusion method. The GC-mass results showed that the ethanolic extract contained several active compounds, including nhexadecanoic acid (37.40%), neophytadiene (11.08%), 9,12,15-octadecatrienoic acid, (Z, Z, Z)-(17.32%), and oleic acid (10.28%). A peak at 435nm in the UV-vis absorption spectrum confirmed the formation of silver nanoparticles. The XRD technique determined the crystalline nature of the silver nanoparticles, and SEM results showed that they had spherical shapes with sizes ranging between 47-78nm. EDX analysis revealed that the synthesized silver nanoparticles comprised silver, carbon, oxygen, and chlorine. The efficacy of the synthesized silver nanoparticles was tested against four types of pathogenic bacteria, namely E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus. The results demonstrated that the silver nanoparticles had a significant inhibitory capability against these pathogens. [ABSTRACT FROM AUTHOR]

The global increase in multidrug-resistant bacteria poses a challenge to public health and requires the development of new antibacterial materials. In this study, we examined the bactericidal properties of mesoporous silica-coated silver nanoparticles, varying the core sizes (ca. 28 nm and 51 nm). We also investigated gold nanoparticles (ca. 26 nm) coated with mesoporous silica as possible inert metal cores. To investigate the modification of antimicrobial activity after the surface charge change, we used silver nanoparticles with a silver core of 28 nm coated with a mesoporous shell (ca. 16 nm) and functionalized with a terminal amine group. Furthermore, we developed a facile method to create mesoporous silica-coated silver nanoparticles (Ag@mSiO2) doped films using polyurethane (IROGRAN®) as a polymer matrix via solution casting. The antibacterial effects of silver nanoparticles with different core sizes were analyzed against Gram-negative and Gram-positive bacteria relevant to the healthcare and food industry. The results demonstrated that gold nanoparticles were inert, while silver nanoparticles exhibited antibacterial effects against Gram-negative (Escherichia coli and Salmonella enterica subsp. enterica serovar Choleraesuis) and Gram-positive (Bacillus cereus) strains. In particular, the larger Ag@mSiO2 nanoparticles showed a minimum inhibitory concentration (MIC) and a minimum bactericidal concentration (MBC) of 18 µg/mL in the Salmonella strain. Furthermore, upon terminal amine functionalization, reversing the surface charge to positive values, there was a significant increase in the antibacterial activity of the NPs compared to their negative counterparts. Finally, the antimicrobial properties of the nanoparticle-doped polyurethane films revealed a substantial improvement in antibacterial efficacy. This study provides valuable information on the potential of mesoporous silica-coated silver nanoparticles and their applications in fighting multidrug-resistant bacteria, especially in the healthcare and food industries. [ABSTRACT FROM AUTHOR]

Electrospun polymeric nanofibers incorporated with some medicines or biologically active nanoparticles have a huge range of various applications in biomedical fields such as wound dressing, drug delivery, and tissue engineering. Blending several polymers with different properties allows one to obtain a new material with improved physicochemical and mechanical characteristics, as well as to control the incorporation and release of medical agents, including antimicrobial, antifungal, and other substances. In this work, a novel approach to prepare a blend of two polymers [polyvinylpyrrolidone (PVP) and polymethyl methacrylate (PMMA)] to produce biocompatible nanofibers with incorporated antibacterial agents — phenylalanine or silver nanoparticles is proposed. The diameter of the obtained nanofibers is in the range of 2–4 μm. Antimicrobial agents are incorporated in PVP in an aqueous solution, then the prepared adduct is dried and mixed with PMMA in an organic solvent. In this nanofiber mat, PMMA provides the mechanical strength of the mat and assists in the gradual release of the antimicrobial agents. The formation of the PVP:PMMA nanofibers with incorporated antimicrobial agents at different stages was monitored by spectroscopy. The release of antimicrobial agents from the nanofibers mat during wetting was studied and confirmed by spectroscopy and mass spectrometry investigations. [ABSTRACT FROM AUTHOR]

Environmentally friendly powder coatings which have the advantages of being VOC-free, low-cost, and high-efficiency with a high recovery rate have been attracting increasing research attention. The introduction of antibacterial agents into the powder coatings endows them with a capacity to kill bacteria and viruses on the surface of objects; additionally, this enables them to inhibit the indirect transmission of pathogenic microorganisms. Silver, possessing broad-spectrum, strong, and stable antibacterial properties, is considered to be a promising antibacterial material for use in coating applications. Carrier materials for active silver play an important role in its activity and stability. However, there is a lack of systematic studies on the effects of different types of carriers in such coating systems, especially in green powder coating systems. In this paper, we investigated two types of carriers for active silver agents: zeolite, i.e., Linde type A (LTA) zeolite and Y-type zeolite; clay-based materials, i.e., montmorillonite and vermiculite. All the agents showed high antibacterial activity, with antibacterial rates of over 99% as compared to commercial agents. Among the four agents, the Ag-LTA zeolite antimicrobial agent showed a reduction rate of over 99.99%; additionally, it maintained a reduction rate of 99% after seven washing cycles. Thus, this agent was demonstrated to have the highest effectiveness and high durability; these features can be attributed to the high silver content and small particle size. The LTA zeolite also provides a protective effect for silver ions, protecting them from reduction, due to the restriction of elemental silver formation within the confined interior space of the α-cage structure. The Y-type zeolite antimicrobial agent exhibited a slightly lower antimicrobial performance due to its higher silicon-to-aluminum ratio and its lower cation exchange capacity. Comparatively, antimicrobial agents utilizing clay-based carriers have lower cation exchange capacity, resulting in poorer antimicrobial effectiveness than zeolite carriers. In addition, silver loaded on clay-based materials is prone to detach from the carrier and undergo a reduction reaction, making the coating yellowish in color. This study first provides information on the roles of different types of carriers in powder coating systems; then, this information guides the selection of carriers for active silver for the development of efficient antimicrobial agents and coatings. [ABSTRACT FROM AUTHOR]

Silver nanoparticles are silver metal particles with a size of less than 100 nm. Extract of epiphytic shrub leaves (Ficus heteropleura Blume) serves as a bioreductant in producing silver nanoparticles, which are utilized for their antibacterial properties against Escherichia coli. This study aims to synthesize silver nanoparticles and assess their activity against Escherichia coli. Silver nanoparticles (AgNPs) were synthesized using the green synthesis method with Ficus heteropleura leaf extract with silver nitrate (AgNO3). AgNPs were synthesized using a 1 mM solution of AgNO3 and different concentrations (2, 4, 6, 8, and 10%) of Ficus heteropleura extract. The AgNPs were characterized using UV-Vis spectrophotometer, FTIR, and PSA. UV-Vis analysis revealed that AgNPs at concentrations ranging from 2% to 10% exhibited absorbance peaks within the wavelength range of 201.2–473.5 nm. FTIR analysis identified functional groups such as OH, CH, C=C, C≡C, C≡N, and CO, which played a role in reducing silver nanoparticles. The size distribution of AgNPs was determined, with AgNPs synthesized at a concentration of 6% exhibiting a size range of 1–100 nm, constituting 40.77% of the total. For AgNPs synthesized at concentrations of 8% and 10%, the percentage of nanoparticles in the 1–100 nm size range was found to be 26.845% and 1.28%, respectively. The antibacterial activity of AgNPs at concentrations of 6% and 8% against Escherichia coli demonstrated moderate effectiveness. [ABSTRACT FROM AUTHOR]