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Biosurfactants prevent agglomeration of nanoparticles by reducing the surface tension and offer stability over time by forming a stable layer on the surface of nanoparticles. The current study focuses on the biosynthesis of silver nanoparticles (SNP) coated with a rhamnolipid biosurfactant (BS) and its use as an additive in fabric cleaning detergent. Rhamnolipids were extracted from a Pseudomonas aeruginosa strain, Pa84, that was isolated from a halophilic environment, Sambhar Salt Lake, Rajasthan, India. The reduction of silver ions was achieved by the rhamnolipid‐coated SNP (BS‐SNP). BS, SNP, and BS‐SNP demonstrated antibacterial efficacy against a variety of microorganisms. Lipase, present in the crude biosurfactant, was immobilized on modified chitosan microbeads (Ch‐BS‐SNP) and used for washing fabrics. The conjugate was found to be effective as a laundry detergent additive. The immobilized lipase showed high relative activity ranging from 66% to 110% and performed better than free lipase or standards. Our results highlight a potential claim for a commercially viable laundry detergent additive. [ABSTRACT FROM AUTHOR]

Nanotechnology has changed and developed all the sectors and working fields. Nanoparticles are one of the important evolutionary materials that have application in almost all the working areas such as catalysis, bioengineering, photoelectricity, antibacterial, anticancer, and medical imaging due to their unique physical and chemical properties. Traditionally used chemical and physical method of synthesis of nanoparticles have several disadvantages like using different chemicals, high cost, and most importantly they are hazardous to the environment. Counter to these disadvantages, a more eco‐friendly, easy, and cost‐effective green synthesis method is widely employed nowadays. Various parts of a plant are used as a fuel for reducing the metal ion salt. Plant extracts act as reducing, stabilizing, and capping agents. Besides these advantages, photosynthesized nanoparticles are nontoxic, more stable, and more uniform in size than their counterparts prepared by the traditional method. In this present review, the synthesis of various plant extract‐mediated metal and metal oxide nanoparticles is discussed along with their different applications. This review provides a comprehensive overview of key findings in green synthesis of metal and metal oxide nanoparticles and attempts to determine their possible synthesis mechanism. This article also focuses on factors affecting their synthesis, characterization, potential applications, and prospects. [ABSTRACT FROM AUTHOR]

Doxycycline (Doxy) is a tetracycline antibiotic with a potent antibacterial activity against a broad range of bacteria. Using nanotechnology is one feasible way to increase the antibiotics' ability to penetrate the body and increase their antibacterial effectiveness. In this work, we report the formation of a stable green synthesized silver nanoparticles (AgNPs) by chitosan with Doxy nanocomposite for the first time. The obtained nanoparticles were characterized by transmission electron microscopy (TEM), zeta-potential, UV-Visible spectroscopy and four transform infrared spectroscopy (FTIRs). The antibacterial effect of doxy, AgNPs and doxy/AgNPs were determined on Gram-positive Staphylococcus aureus, Streptococcus mutans and Gram-negative Escherichia coli, Klebsiella pneumonia. This combined therapeutic agent restored the susceptibility of doxy and showed an antibacterial activity against tested bacteria. AgNPs has absorption peak at 445 nm, mixing of Doxy with AgNPs causes all doxy absorptions to red shift and a broadening in surface plasmon resonance (SPR) for AgNPs and show a slight increase in particle size of AgNPs from 12 ± 2 nm to 14 ± 2 nm with high stability as zeta potential was 29 mv and 48.5mv for AgNPs and Doxy/AgNPs respectively. The antibacterial effect of Doxy/AgNPs nanocomposite was found to be twice effect of free doxy, suggesting a synergistic interaction between the two components. In conclusion, synergy of doxy with AgNPs is quite promising for antibiotic resistant strains. These results highlight the ability of AgNPs to boost the efficacy of the doxycycline. [ABSTRACT FROM AUTHOR]

Catalytic conversion of CO2 into value‐added chemicals is necessary to mitigate the increasing global warming and energy‐related issues. The selective production of C2 or C2+ products by photoreduction of CO2 is a challenging task due to the sluggish kinetics of C─C coupling. Herein, the potential of a silver nanoparticle (Ag NP) incorporated metal‐organic framework (MOF), NU‐1000 is introduced, to harvest light and ease the uphill electron transfer. The growth of silver nanoparticles on thiol‐functionalized NU‐1000 is studied using the atomic pair distribution function (PDF) analysis. The C2 product formed using Ag@NU‐1000‐SH without any sacrificial agents is acetic acid, which is confirmed by 1H‐NMR and HRMS data. The catalyst displays a high acetate output of 293.58 µmolg−1h−1 with a selectivity of 79.4%. The XPS and DFT calculations evidence that the presence of the charge‐polarised states in the as‐synthesized catalyst act as asymmetric centers that favor the C─C coupling reaction. The combined experimental (in situ DRIFT spectroscopic studies) and theoretical calculations reveal that the C─C coupling takes place via the coupling of COOH*intermediates. [ABSTRACT FROM AUTHOR]

The effect of surface modification of polystyrene plates for immunoassay with silver nanoparticles and polyelectrolytes on the fluorescent signal of adsorbed antibodies with fluorescent labels IgG-FITC, IgG-AF488 and IgG-AF647 was studied. The resulting solid phase was characterized by a sorption capacity increased by 30–50% as compared to high-binding polystyrene (Greiner, Austria) and the ability to enhance the fluorescent signals of the labels due to a plasmonic effect, which together increased the fluorescence intensity by 3–15 times, depending on the type of plate surface, the nature of the polyelectrolyte, and the optical and physicochemical properties of the labeled antibodies. [ABSTRACT FROM AUTHOR]

In the present study, the effects of methyl jasmonate (MeJA) and silver nanoparticles (AgNPs) on Salvia nemorosa L. were evaluated under NaCl stress. To this end, total soluble sugar content, total phenolic and flavonoid contents, total antioxidant capacity, H2O2 content, photosynthetic pigment content, malondialdehyde (MDA) content, proline content, and enzymatic antioxidant activities were assessed. When the results for photosynthetic pigment content were evaluated, the highest levels of total carotenoid content, chlorophyll a, and chlorophyll b were obtained with NaCl + AgNP + MeJA treatment. Under NaCl stress, MDA and H2O2 levels increased, but they decreased when AgNP and MeJA were applied. All treatment groups had higher proline contents than the control group; the NaCl + AgNP + MeJA treatment group had the lowest content, while the NaCl treatment group had the highest. The combined elicitor treatment had little effect on total soluble sugar content. The combined elicitor treatment significantly increased total phenolic and flavonoid contents compared to separate applications. The most effective treatment for scavenging DPPH radicals was NaCl + MeJA, whereas the most effective treatment for scavenging CUPRAC and ABTS radicals was NaCl + MeJA + AgNP. Treatmentrelated variations were observed in enzyme activities; NaCl + MeJA + AgNP treatment caused the greatest increases in SOD, CAT, and APX activities, whereas NaCl + MeJA treatment resulted in the maximum GR activity. Compared to treatment with NaCl alone, the combined application of AgNP and MeJA improved some physiological and biochemical indices and increased plant resistance to salt stress. The synergistic impact of AgNP and MeJA on reducing the effects of salt stress in Salvia nemorosa L. suggests that these two compounds may strengthen plant resilience under adverse environmental conditions. [ABSTRACT FROM AUTHOR]

In this study, we explore the synthesis of silver nanoparticles (AgNPs) using calyx wastes from Abelmoschus esculentus (okra) and evaluate their anthelmintic potential against poultry pathogen Raillietina spp. The ultraviolet‐visible (UV‐vis) spectrum of nanoparticles showed an absorbance peak at 425 nm, confirming AgNP formation. Fourier transform infrared spectrophotometry (FTIR) analysis indicated the presence of functional groups responsible for reducing silver ions, and X‐ray diffraction (XRD) patterns confirmed the crystallinity of the nanoparticles. Dynamic light scattering (DLS), scanning and transmission electron microscopy (SEM and TEM) analyses were used to measure the size (20–50 nm) and morphology (spherical) of the synthesized AgNPs. The dose‐dependent in vitro anthelmintic efficacy was highest at 125 μg/ml of AgNPs, resulting in paralysis and death within 0.54 and 1.29 hours, respectively, while untreated control parasites survived for ~72 hours. The SEM micrographs of the treated parasites showed swelling and blebbing of the tegument. Histochemical localization studies showed a remarkable decline of tegumental and neurotransmitter enzymes involved with the parasite's metabolism and regulation of the endogenous physiological processes. This study underscores the potential of okra calyces in the green synthesis of AgNPs and provides a novel approach to developing alternative anthelmintics that interfere with the host‐parasite interface. [ABSTRACT FROM AUTHOR]

This study implements research-oriented comprehensive chemistry laboratory teaching by combining fundamental education with scientific research training, thus enhancing talent development and promoting educational reform harmoniously. Silver nanoparticles were synthesized using straightforward inorganic chemical reactions, with the color of the resulting silver nanocolloid solution controlled by varying the bromine/silver ratio. This introduction of surface plasmon resonance characteristics into the experimental curriculum increases the experiment's engagement. The chemical activity of the silver nanoparticles was verified using the classic p-nitrophenol catalytic reaction model. Results indicated that the silver nanoparticles exhibited excellent catalytic performance, approximating first-order reaction kinetics. Additionally, a simple pollutant degradation reactor was constructed using standard laboratory glassware, and homemade silver-embedded filter paper was used for over ten cycles of degradation, achieving a degradation rate of up to 90%. [ABSTRACT FROM AUTHOR]

In printed electronics, nanosecond pulsed laser scanning ablation is used to repair misprinted conductive silver (Ag) nanoparticle (NP) lines. Nanosecond-pulsed laser ablation is a thermal process influenced by the thermal dissipation of the substrate. In this study, we investigated the influence of the thermal properties of the substrate on the scanning ablation of Ag NP layers using a 532 nm Nd:YAG laser. We examined the ablation aspects of nanosecond pulsed scanning ablation of Ag NP layers on polyimide (PI), glass, and crystalline silicon (Si) substrates. The dried Ag NP layers and Ag NP layers that were sintered at 100, 150, and 200 °C were compared. No significant difference was observed between the ablation thresholds of the Ag NP on PI and glass substrates at all sintering temperatures. However, when the sintering temperature was 150 and 200 °C, the ablation thresholds of Ag NP on Si substrate were 371 and 435 mJ/cm2, which are noticeably larger than the 284 and 355 mJ/cm2 of 150 and 200 °C sintered Ag NP on PI substrate and 273 and 349 mJ/cm2 of 150 and 200 °C sintered Ag NP on glass substrate. Qualitative and quantitative explanations of the observed trends were provided. [ABSTRACT FROM AUTHOR]

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

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

The aquatic environment, independent of their host, is more favorable to pathogenic bacteria than the terrestrial environment. Consequently, pathogenic bacteria can reach very high densities around aquatic animals and can cause high mortality. The conventional approach, such as antibiotics, has minimal effectiveness. Additionally, due to the emergence of (multiple) resistance, their use is under intense scientific and public scrutiny. Hence, there is a need for the development of alternative control techniques, with an emphasis on prevention, which is likely to be more cost-effective. In this study, a potential bacterial strain Cytobacillus firmus was isolated from polluted river sediment and characterized using a comprehensive range of techniques including biochemical, 16S rRNA sequencing and antibiogram assay. The pathogenicity of the bacteria was tested in vivo on Labeo rohita fingerlings found as non-pathogenic. Further, the bacteria were found to synthesize silver nanoparticles (AgNPs) using AgNO3 as a substrate. The obtained AgNPs were characterized by various methods, including UV-vis spectroscopy, FTIR (Fourier-transform infrared spectroscopy), and Transmission Emission Microscopy (TEM). The study found that the AgNPs were 20 nm in size on average. The antimicrobial activity of synthesized AgNPs was examined against the model freshwater pathogenic bacteria, Edwardsiella tarda and both the MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericidal Concentration) were 0.156 µM, while biofilm inhibition activity was also observed at 0.156 µM. The AgNPs showed no haemolytic activity at 0.313 µM. Our findings suggest that C. firmus mediated bacteriogenic AgNPs modulate the activity of common pathogenic bacteria E. tarda. The thoroughness of our research process gives us confidence in the potential of applying AgNPs in aquaculture as a considerable strategy to control the E. tarda infection. [ABSTRACT FROM AUTHOR]

The green synthesis of noble metal nanoparticles has gained a lot of interest in the area of nanotechnology, because of its high therapeutic properties. The present study focussed on the synthesis of the silver nanoparticles (Ag-NPs) using Ceropegia debilis leaf extract and characterized by various physio-chemical techniques and surface morphological studies. The prepared Ag-NPs exhibit a face-centred cubic structure, spherical morphology, and high purity as shown by XRD, SEM, and EDS analyses. The average size of the Ag-NPs was confirmed by TEM study as 18.6 ± 7.5 nm. The synthesized Ag-NPs show remarkable antioxidant activity of 72.1% compared to standard BHT 86.9%. Furthermore, Ag-NPs show remarkable cytotoxic properties against MCF 7 and A 549 cell line of 37.19% and 33.33%, respectively at 250 µg/mL. The antibacterial activity of Ag-NPs was investigated against the human pathogen and intestinal pathogen Staphylococcus aureus and Escherichia coli by agar disc diffusion method. Moreover, the synthesised Ag-NPs exhibit good antifungal properties against the fungal specimen Trichoderma viride assessed by well diffusion technique. In addition, Ag-NPs serve as an excellent nanocatalyst in the removal of toxic methylene blue dye (93.2%) from industrial wastewater under sunlight irradiation. [Display omitted] • Silver nanoparticles were synthesized by Ceropegia debilis extract. • SEM and TEM used for surface morphology and size determination. • Impressive anti-proliferative activity towards MCF 7 and A 549 were observed. • Effective nanocatalyst for the degradation of methylene blue dye. [ABSTRACT FROM AUTHOR]

BACKGROUND: Surface roughness of arch wires directly impacts their corrosion behavior, friction resistance, and plaque accumulation, which may hinder tooth movement and lead to dental caries. OBJECTIVES: The study aims to synthesize vanillin-mediated silver nanoparticles (AgNPs), characterize them, assess surface roughness and cytotoxicity of arch wires after silver nanoparticle coating, and test their antibacterial properties. MATERIALS AND METHODS: Nine copper–nickel–titanium arch wires (CuNiTi) were cut into equal pieces. Three were sent for surface roughness assessment, three for cytotoxicity, and three for antibacterial testing. Dip coating of wires was done using the sol–gel thin film method. The surface roughness (Ra) before and after coating was evaluated using scanning electron microscopy and atomic force microscopy. Cytotoxicity testing was done with a (3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay using gingival fibroblasts. Statistical analysis was done using SPSS software. Antibacterial activity against S. mutans was tested using the Agar-well diffusion method. RESULTS: The CuNiTi wires were coated successfully, and the coating appeared homogeneous. The mean Ra after coating (297.3+/- 30.4 nm) was significantly less than that before coating (339.7+/-49.2 nm). AgNPs showed minimal cytotoxicity against human gingival fibroblasts at different concentrations. Optical microscopy showed over 90% viability between 12.5 and 100 µg/ml. At 100 µg/ml, only 80% of cells remained viable. AgNP coating is biocompatible at concentrations up to 75 µg/ml. There was a significant intergroup difference in the zone of inhibition (antibacterial activity) noted with higher values in noncoated wires. (P value <0.007). CONCLUSION: AgNPs coated on CuNiTi arch wires showed reduced surface roughness and minimal cytotoxic effects on human gingival cells and good antibacterial activity against S. mutans compared to noncoated arch wires. [ABSTRACT FROM AUTHOR]

Due to the rising human population and industrialization, harmful chemical compounds such as 4-nitrophenol (4-NP) and various dyes are increasingly released into the environment, resulting in water pollution. It is essential to convert these harmful chemicals into harmless compounds to mitigate this pollution. This research focuses on synthesizing a novel heterogeneous catalyst using modified canvas fabric (CF) decorated with silver metal nanoparticles on graphene oxide nanosheets (Ag-GO/CF). The process involves coating the fabrics (CF) with graphene oxide (GO) nanosheets through sonication. Subsequently, silver nanoparticles are deposited in situ and reduced on the GO surface, resulting in the formation of the Ag-GO/CF composite. Various physicochemical characterizations were conducted to examine the interfacial interactions between CF, GO, and Ag nanoparticles. The catalytic activity of the nanocomposite was assessed by hydrogenating 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of sodium borohydride (NaBH4). The results showed that the 10%Ag-5%GO/CF with a surface of 6 cm2 (3 × 2 cm) exhibited the highest catalytic activity, achieving a reduction efficiency of over 96% in 5 min. The 4-NP reduction reaction rate was well-fitted with a pseudo-first-order kinetics model with an apparent reaction rate constant (Kapp) of 0.676 min−1. Furthermore, the Ag-GO/CF composite demonstrated remarkable stability over successive cycles, with no noticeable decrease in its catalytic activity, suggesting its promising application for long-term chemical catalytic processes. This synthesized composite can be easily added to and removed from the reaction solution while maintaining high catalytic performance in the reduction of 4-NP, and it could be beneficial in avoiding problems related to powder separation. [ABSTRACT FROM AUTHOR]

To study the antibacterial efficacy of metallic Ag nanoparticle/titania (Ag‐NP)/TiO2 composite thin films against Escherichia coli (ATCC 25922), COMP‐Agn with various amounts of Ag (10 mol% ≤ n ≤ 80 mol%) are fabricated on a quartz glass substrate at 600 °C using the molecular precursor method. The films are characterized by X‐ray diffraction, X‐ray photoelectron, scanning electron microscopy, transmission electron microscopy, photoluminescence, and UVvis techniques. The analysis reveals that the films are composed of metallic Ag‐NPs embedded in a mixture of anatase and rutile matrix, with a volumetric fraction of Ag ranging from 0.18 to 0.68. The antibacterial activity of the TiO2 thin film and COMP‐Agn are determined by disk diffusion and viable cell count methods. Neither pure TiO2 nor pure Ag films exhibit any discernible antibacterial under dark and visible light. The antibacterial of Ag content in composite films is observed to persist for a maximum increase of 70%. The model is proposed on the basis of photoexcited electron transfer from Ag NPs to the TiO2 conduction band of COMP‐Agn, which clarifies the main factors affecting the photoresponse and the excellent response to visible light via surface plasmon resonance. [ABSTRACT FROM AUTHOR]

Evaluation of the effects of nanomaterials in various habitats and living groups is increasing with in vitro and in vivo studies. This study aims to describe a biological procedure to synthesize silver nanoparticles using an extract of Marrubium astracanicum and to determine the aquatic environment's oxidative stress on Artemia salina. Silver nanoparticle formation was visually observed with color change. Its structural properties, such as size, shape, morphology, and stability, were characterized by UV-Vis spectrophotometer, TEM, SEM, XRD, and DLS analyses. TEM image showed that the synthesized AgNPs have a size of between 20 and 50 nm. The effects of biosynthesized silver nanoparticles at different concentrations (control,0.2, 1, 5, 10, 25, and 50 mg/mL) and exposure times (24, 48 and 72 h) on total glutathione (GSH) and lipid peroxidation levels (MDA) were investigated on the Artemia salina organism, which is one of the most common saltwater organisms frequently used in ecotoxicity tests. [ABSTRACT FROM AUTHOR]

Background and Aims: The increase in the incidence of antimicrobial resistance in pathogens has led researchers to identify new and effective antimicrobial agents. Green production of nanoparticles has received attention due to its compatibility with the environment and low cost. The present study sought to characterize and evaluate the antibacterial activities of silver nanoparticles synthesized with Plantago lanceolata seed extract. Materials and Methods: In this study, after the synthesis of silver nanoparticles by chemical and green methods, the characteristics of silver nanoparticles synthesized with the P. lanceolata seed extract were evaluated by UV-Vis, DLS, XRD, FT-IR, and TEM methods. Thereafter, the optimal conditions for the synthesis of nanoparticles and the antibacterial activity of the P. lanceolata extract, chemical silver nanoparticles, and green silver nanoparticles against standard bacterial strains were investigated by determining the minimum inhibitory concentration (MIC) using the broth microdilution method. Results: Based on the absorption spectrum of green silver nanoparticles with UV-Vis, the optimal concentration of silver nitrate was 20 mM, the suitable synthesis temperature was 57 °C, and the best reaction time was reported as 30 sec. The results of XRD, FT-IR, and TEM analyses confirmed the synthesis of green silver nanoparticles with oval and spherical morphology with a size of 20-40 nm. The P. lanceolata extract and chemical silver nanoparticles had no significant antibacterial effect. Nonetheless, green silver nanoparticles had significant antibacterial activity on the studied bacteria, with the highest antibacterial effect against Staphylococcus aureus and Enterococcus faecalis (MIC=125 μg/mL). Conclusion: As evidenced by the obtained results, P. lanceolata seed extract significantly increased the antibacterial activity of silver nanoparticles. This research demonstrated the potential of environmentally friendly silver nanoparticles synthesized in the presence of P. lanceolata extract with significant antibacterial effects for various biomedical applications. [ABSTRACT FROM AUTHOR]

Envenomation by Russell's viper [Daboia russelii (Shaw & Nodder, 1797)] is a major medical emergency in tropical countries. The antivenom therapy is a conventional remedy for such medical emergency, but it has limitations and side effects. Nanomedicine and nanotechnology are the most prospective areas of research in the current scenario. In the present study, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of crudeDaboia russelli venom (VRV) was performed. Alginic acid-based silver nanoparticles (AgNP-ALG) were synthesized and characterized using UV-Visible spectroscopy, Dynamic Light Scattering (DLS), Scanning electron microscope (SEM), and X-ray diffraction analysis (XRD). SNPs have average hydrodynamic size of 80.30 nm with 0.271 PDI. X-ray diffraction analysis of AgNP-ALG, which confirmed the cubic crystal shape of silver. SEM studies of AgNP-ALG showed particle sizes ranging from 10 to 50 nm. Spectroscopic analysis showed a decrease in the absorbance intensity of venom upon interaction with AgNP-ALG, indicating interaction with venom proteins. From the data available from fluorescence spectroscopy, it is evident that viper venom preincubated with AgNP-ALG causes quenching of fluorescence intensity. The results obtained by direct hemolytic assay,proteolytic activity and blood clotting test revealed venom action inhibition due to silver nanoparticles. Thus, in the present study we have emphasized that silver nanoparticles inhibit the action of Daboia russelli venom in vitro. [ABSTRACT FROM AUTHOR]

The biological method for silver nanoparticle synthesis emphasizes green synthesis, which is faster, environmentally safer, facile, energy-efficient, and cost-effective. It provides good alternatives to physical and chemical methods. In this research, we have synthesized silver nanoparticles using D. vitifolius ethanolic extract. The 38 natural compounds of flavonoid, phenolic or polyphenol compositions have been determined by LC-MS/MS-QTOF which is carried out using UNIFI software equipped with a mass spectrum library of active substances from natural ingredients from the Waters database. Silver nanoparticle (Dv-AgNP) was characterized by using TEM and SEM where the average diameter of nanoparticle was seen <100 nm and confirmed by PSA analysis that the Z-average is 62.73 ± 0.71 nm. EDS spectrum confirmed the silver element as a major element of the particles. PI value of Dv-AgNP is 0.557, while the zeta potential is - 17.37 ± 1.53 mV. Dv-AgNP can inhibit the growth of P. aeruginosa (amoxicillin resistant) with an inhibition zone of 15.83 ± 2.36 mm, and K. pneumoniae with an inhibition zone is 10.03 ± 0.55 mm. These are moderate inhibitory activities. The antioxidant result of the Dv-AgNP suspension solution shows that the IC50 is 0.58 mM. The IC50 of the crude extract is 752 ppm and is categorized as very weak antioxidant activity. [ABSTRACT FROM AUTHOR]

Background: Over the past two decades, Silver Nanoparticles (AgNPs) have demonstrated a wide range of antioxidant and anticancer properties. Vinca alkaloid exhibits the anticancer efficacy by direct metaphase arrest of cell division. Aim: The present study is to develop a green synthesis method for producing silver nanoparticles using vinca, the antioxidant and anticancer potential was assessed using A549 cells. Materials and Methods: The synthesized AgNPs were analyzed using Fourier Transform Infrared (FTIR) analysis, UV-visible spectrophotometer (UV), Scanning Electron Microscope (SEM) and Spectra Max i3X energy-dispersive X-ray (XRD) Spectroscopy to determine their physico-chemical and morphological characteristics. Results and Discussion: The FTIR spectrum of vinca AgNPs exhibited absorption bands at 692 cm-1, 684 cm-1, 611 cm-1, 592 cm-1, 578 cm-1, 554 cm-1, 548 cm-1, 539 cm-1 and 526 cm-1, indicating the presence of silver ion bounded nanoparticles derived from Vinca leaf. These findings suggest that vinca-coated AgNPs possess multiple functions that contribute to their stability. XRD data analysis revealed Bragg's reflections in the XRD pattern (2θ) at 24.75, 31.59, 37.56, 53.01, 64.93 and 76.27, confirming the crystalline nature of the green synthesized AgNPs. Elemental analysis was conducted to determine the elemental composition of the sample, which indicated that approximately 60% of the prepared nanoparticles were bound with silver ions, supporting the formulation. Antioxidant studies were performed using the DPPH assay at different concentrations of AgNPs, while cell-based cytotoxic assays were conducted using different concentrations of AgNO3. Conclusion: The results demonstrated that the nanoparticles inhibited the proliferation of A549 cells and reduced cellular motility, indicating their promising anticancer efficacy. [ABSTRACT FROM AUTHOR]

This research focuses on the application of nanocellulose-stabilized silver nanoparticles (AgNPs) as a colorimetric sensing probe for mercury (II) detection. For this purpose, cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs) were employed with dual functions: a stabilizing agent and a dispersing matrix. The chemical and structural properties of the samples were analysed by various techniques such as XRD, FTIR, TEM and UV–Vis Spectroscopy. Due to different morphologies and surface functional groups in each type of nanocellulose, their effects on the AgNP formation as well as their response against mercury (II) ions were studied. It was discovered that the AgNPs stabilized by both types of nanocellulose can provide high sensitivity and selectivity towards mercury (II) ions. However, some interference caused by iron (III) ions was observed. This interference could be significantly reduced if the CNFs were employed during the AgNP preparation. Therefore, the advantage of using the CNFs as a stabilizing agent as well as a dispersing matrix will be discussed in detail. Furthermore, the possibility of fabrication into solid-state platforms (nanopapers) and response to mercury (II) ions will be demonstrated. [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]

Cassava root rot disease caused by the fungal pathogens Fusarium solani and Lasiodiplodia theobromae produces severe damages on cassava production. This research was conducted to produce and assess silver nanoparticles (AgNPs) synthesized by Trichoderma harzianum for reducing root rot disease. The results revealed that using the supernatants of T. harzianum on a silver nitrate solution changed it to reddish color at 48 h, indicating the formation of AgNPs. Further characterization was identified using dynamic light scattering (DLS) and scanning electron microscope (SEM). DLS supported that the Z-average size is at 39.79 nm and the mean zeta potential is at − 36.5 mV. SEM revealed the formation of monodispersed spherical shape with a diameter between 60–75 nm. The antibacterial action of AgNPs as an antifungal agent was demonstrated by an observed decrease in the size of the fungal colonies using an increasing concentration of AgNPs until the complete inhibition growth of L. theobromae and F. solani at > 58 µg mL−1 and at ≥ 50 µg mL−1, respectively. At in vitro conditions, the applied AgNPs caused a decrease in the percentage of healthy aerial hyphae of L. theobromae (32.5%) and of F. solani (70.0%) compared to control (100%). The SR-FTIR spectra showed the highest peaks in the first region (3000–2800 cm−1) associated with lipids and fatty acids located at 2962, 2927, and 2854 cm−1 in the AgNPs treated samples. The second region (1700–1450 cm−1) consisting of proteins and peptides revealed the highest peaks at 1658, 1641, and 1548 cm−1 in the AgNPs treated samples. The third region (1300–900 cm−1), which involves nucleic acid, phospholipids, polysaccharides, and carbohydrates, revealed the highest peaks at 1155, 1079, and 1027 cm−1 in the readings from the untreated samples. Finally, the observed root rot severity on cassava roots treated with AgNPs (1.75 ± 0.50) was significantly lower than the control samples (5.00 ± 0.00). [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is a leading cause of morbidity and death worldwide. As current cancer drugs are ineffective, new solutions are being sought in other fields, including nanoscience. Similarly, silver nanoparticles play an important role in the pharmaceutical industry as they act as anti-cancer agents with less harmful effects and are usually 1 to 100 nm in size. Selenic acid (SA) and pyruvic acid (PA) are involved in various metabolic pathways in cancer. For this reason, we decided to detect their influence on colorectal cancer using silver-based (Ag) nanocarriers. DLS, Zetasizer, SEM and UV-Vis analyses were used to characterize AgSA and AgPA. A UV spectrophotometer was used to analyze the release of the NPs. MTT analyses were used to measure the viability of HCT116 and HUVEC cells, and IC50 values were calculated using GraphPad Prism. The indicated dosage and particle size of AgSA NPs proved to be suitable for cytotoxicity. Moreover, injection of these nanoparticles into non-cancer cells proved safe due to their minimal toxicity. In contrast, the AgPA NPs have no cytotoxicity and induce proliferation of HCT116 cells. Finally, only the synthesised AgSA nanoparticles could be used for advanced cancer therapy, which is both inexpensive and has minimal side effects. [ABSTRACT FROM AUTHOR]

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Nanotechnology and nanoparticles have gained massive attention in the scientific community in recent years due to their valuable properties. Among various AgNPs synthesis methods, microbial approaches offer distinct advantages in terms of cost-effectiveness, biocompatibility, and eco-friendliness. In the present research work, investigators have synthesized three different types of silver nanoparticles (AgNPs), namely AgNPs-K, AgNPs-M, and AgNPs-E, by using Klebsiella pneumoniae (MBC34), Micrococcus luteus (MBC23), and Enterobacter aerogenes (MBX6), respectively. The morphological, chemical, and elemental features of the synthesized AgNPs were analyzed by using UV-Vis spectroscopy (UV-Vis), Fourier transform-infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and energy-dispersive spectroscopy (EDX). UV-Vis absorbance peaks were obtained at 475, 428, and 503 nm for AgNPs-K, AgNPs-M, and AgNPs-E, respectively. The XRD analysis confirmed the crystalline nature of the synthesized AgNPs, having peaks at 26.2°, 32.1°, and 47.2°. At the same time, the FTIR showed bands at 599, 963, 1,693, 2,299, 2,891, and 3,780 cm−1 for all the types of AgNPs indicating the presence of bacterial biomolecules with the developed AgNPs. The size and morphology of the AgNPs varied from 10 nm to several microns and exhibited spherical to porous sheets-like structures. The percentage of Ag varied from 37.8% (wt.%) to 61.6%, i.e., highest in AgNPs-K and lowest in AgNPs-M. Furthermore, the synthesized AgNPs exhibited potential for environmental remediation, with AgNPs-M exhibiting the highest removal efficiency (19.24% at 120 min) for methyl orange dye in simulated wastewater. Further, all three types of AgNPs were evaluated for the removal of methyl orange dye from the simulated wastewater, where the highest dye removal percentage was 19.24% at 120 min by AgNPs-M. Antibacterial potential of the synthesized AgNPs assessment against both Gram-positive (GPB) Bacillus subtilis (MBC23), B. cereus (MBC24), and Gram-negative bacteria Enterococcus faecalis (MBP13) revealed promising results, with AgNPs-M, exhibiting the largest zone of inhibition (12 mm) against GPB B. megaterium. Such investigation exhibits the potential of the bacteria for the synthesis of AgNPs with diverse morphology and potential applications in environmental remediation and antibacterial therapy-based synthesis of AgNPs. [ABSTRACT FROM AUTHOR]

The synthesis of silver nanoparticles (AgNPs) holds significant promise for various applications in fields ranging from medicine to electronics. Accurately predicting the particle size during synthesis is crucial for optimizing the properties and performance of these nanoparticles. In this study, we compare the efficacy of tree-based models compared with the existing models, for predicting the particle size in silver nanoparticle synthesis. The study investigates the influence of input features, such as reaction parameters, precursor concentrations, etc., on the predictive performance of each model type. Overall, this study contributes to the understanding of modeling techniques for nanoparticle synthesis and underscores the importance of selecting appropriate methodologies for accurate particle size prediction, thereby facilitating the optimization of synthesis processes and enhancing the effectiveness of silver nanoparticle-based applications. [ABSTRACT FROM AUTHOR]

Malachite green dye adsorption from aqueous solution using silver nanoparticle (AgNP) stabilized with sodium tripolyphosphate cross-linked chitosan is reported in this study. Silver nanoparticle prepared was characterized by Fourier transform Infra-red spectroscopy (FTIR), X-ray diffractometry (XRD), UV-visible spectrophotometer and Scanning electron microscopy (SEM). The crystalline nature of the AgNP was revealed with XRD. The cubic facecentered structure of the synthesized silver nanoparticle was confirmed. This was supported by the observed sharp four diffraction peaks with peaks intense appeared at 2θ = 38.09°, 44.15°, 64.67°, and 77.54°. However, the SEM micrograph of the synthesized AgNP revealed the spherical shape of AgNP with a non-uniform granular shape attributed to biomediated ionic gelation process. The surface of the synthesized AgNP has a spherical shape and slightly elongated with a big tendency to aggregate and form larger particle clusters. Whereas, FTIR spectra of AgNP gave peaks at 1054 - 1645 cm-1 suggesting the presence of phosphonate linkages between ammonium, -NH3+ of chitosan and --PO32- moieties of NaTPP during cross linking process. The adsorption study was carried out under different conditions such as, pH, adsorbent dosage, contact time, temperature and initial concentration of dye to determine the best conditions and the maximum adsorption capacities. The results indicated that increase in temperature had very minimal effect on the adsorption process. The silver nanoparticle was effective in the removal of malachite green in acidic medium. This observation may be due to strong adsorption of the dye on the acidic surface of silver nanoparticle adsorbent by an acid-base interaction mechanism between the adsorbents and the adsorbates. Thus, the adsorption mechanism can be best described by electrostatic interaction. Langmuir, Freundlich and Tempkin model gave a better fit to adsorption isotherms while Dubinin Radushkevich model is not appropriate for the adsorption process. The results obtained from this study indicate that silver nanoparticle could be utilized as effective adsorbents for the removal of dyes from aqueous solution. [ABSTRACT FROM AUTHOR]

Novel formulations of silver nanoparticles remain exciting if it is applicable for cosmetic purposes. This study proposes a value-added brand-new nanomaterial for improving skin complexion by inhibiting melanin development. This work aims to develop cost effective, efficient, natural silver nanoparticles phytomediated by aqueous extract of leaf sheath scales of Cocos nucifera (Cn-AgNPs) having potential as tyrosinase inhibitors hindering melanin synthesis. The formation of Cn-AgNPs was assessed spectrophotometrically and confirmed by the sharp SPR spectrum at 425 nm. The chemical composition profiling was characterized by X-ray diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy. The morphology was confirmed by Field Emission Scanning Electron Microscopy (FESEM) and the thermal stability was assessed by Thermogravimetric analysis (TGA). Pharmacological application studies supported the materialization of Cn-AgNPs with significant antityrosinase potential and considerably improved antibacterial and antioxidant properties. Cn-AgNPs showed potential antibacterial effects against gram-positive and negative strains, including prominent infectious agents of the skin. Antioxidant capacity was confirmed with an IC50 of 57.8 μg/mL by DPPH radical scavenging assay. Furthermore, in vitro melanin content determination was performed using SK-MEL cells. Cell line studies proved that Cn-AgNPs decrease the melanin content of cells. The IC50 value obtained was 84.82 μg/mL. Hence Cn-AgNPs is proposed to be acting as a whitening agent through lessening cellular melanin content and as a significant inhibitor of tyrosinase activity. The antioxidant properties and antibacterial effects can contribute to skin rejuvenation and can prevent skin infections as well. This evidence proposes the development of a new nanostructured pharmaceutical and cosmetic formulation from Cocos nucifera leaf sheath scales. [ABSTRACT FROM AUTHOR]

Background: Nonessential heavy metals pose a significant threat to human health due to their toxicity. Mercury, in particular, is identified as a hazardous metal. The study aims to detect mercury using colorimetric analysis with Murraya koenigii, emphasizing the eco-friendliness of the method. Aims and Objectives: The primary objective is to detect mercury using a colorimetric analysis method employing Murraya koenigii. Additionally, the study aims to investigate the eco-friendliness of this detection method. Materials and Methods: Colorimetric analysis was conducted using Murraya koenigii to detect mercury. Ultraviolet-visible (UV-vis) spectroscopy was employed to detect the formation of silver nanoparticles (AgNPs), with a characteristic surface plasmon resonance (SPR) band observed. X-ray diffraction (XRD) data analysis was performed to determine the crystalline nature and size of AgNPs. Scanning electron microscopy (SEM) was utilized to visualize the morphology of AgNPs. Fourier transform infrared (FTIR) spectroscopy was employed to identify functional groups involved in reducing silver ions. Antibacterial properties of synthesized AgNPs were tested against various microorganisms, including Escherichia coli, Staphylococcus aureus, Streptococcus mutans, and Enterococcus faecalis. Results: Mercury was successfully detected using colorimetric analysis with Murraya koenigii. Formation of AgNPs was confirmed by UV-vis spectroscopy, with a characteristic SPR band at 418 nm. AgNPs were found to be crystalline with an average size of 5.20 nm, as determined by XRD analysis. SEM images revealed spherical and polycrystalline AgNPs. FTIR spectra indicated the involvement of the -OH group of compounds in the extract in reducing silver ions. Synthesized AgNPs exhibited antibacterial properties against various microorganisms. Conclusion: A sustainable and eco-friendly method for synthesizing AgNPs using Murraya koenigii extract was successfully developed. This method not only detected mercury but also demonstrated antibacterial properties against various microorganisms. The study underscores the health implications of nonessential heavy metals, emphasizing the importance of eco-friendly detection and mitigation methods. [ABSTRACT FROM AUTHOR]

Nonessential heavy metals are toxic to human health. In this study, mercury, a hazardous metal, was detected by colorimetric analysis using Murraya koenigii. The eco-friendliness of this method was also emphasized. UV spectrum is a broad peak observed at 200-250 nm in P. guajava leaf extracts. The UV spectrum of green synthesized P. guajava exhibited an absorption band of 418 nm, which confirms the nanoparticle synthesis. FTIR analysis of the vibrational peak around 3307 cm-1 is assigned to ?(O-H) stretching that could possibly emanate from carbohydrates or phenolics. The peaks found around 2917 and 2849 cm-1 are ascribed to the -C-H stretch of the alkyl group, and the peak around 1625 cm-1 is due to the enolic ß-diketones or -C = O stretch of carboxylic acids, while the corresponding -C-O stretch is observed around 1375 and 1029 cm-1. The assignment of peaks is similar. It is clear from the SEM image that the constituent parts were non-uniform sphere-shaped, agglomerated, and of an average size of 30.9 nm. XRD analysis was utilized to determine the structural characteristics and crystalline nature of P. guajava. The observed intensity peaks at 32.35°, 36.69°, 39.24°, 44.76°, 59.42°, and 67.35° represent the 2? values for P. guajava in the diffraction pattern, aligning with the values in the standard database. The synthesized AgNPs tested antibacterial properties against various strains of microorganisms, including Escherichia coli, 25 µg/mL 6.02 ± 0.17 and 100 µg/mL 7.3 ± 0.05, Staphylococcus aureus, 25 µg/mL 05.02 ± 0.07 and 100 µg/mL 11.3 ± 1.12, Streptococcus mutans, 25 µg/mL 04.02 ± 0.19 and 100 µg/mL 11.1 ± 0.11, Enterococcus faecalis, 25 µg/mL 0.8.05 ± 0.11 and 100 µg/mL 11.7 ± 0.02. The short novelty of Psidium guajava (guava) lies in its potential relevance to human health, as it has been found to possess bioactive compounds with various medicinal properties, such as antimicrobial, antioxidant, and anti-inflammatory activities, making it a promising natural resource for therapeutic applications. [ABSTRACT FROM AUTHOR]

Nanotechnology is developing into a fast-expanding discipline with applications in science and technology, and nanostructures are a crucial research tool in many fields. Due to their remarkable electrical, optical, magnetic, catalytic, and pharmacological capabilities, metal and metal oxide nanoparticles (NPs) have drawn study interest. Natural elements (plants, microorganisms, fungi, etc.) are utilized in a chemical-free, environmentally benign way to synthesize metals and metal oxides. The optical, electrical, and antimicrobial qualities of silver nanoparticle (AgNP) make them a popular choice. More than 200 active ingredients, including water-soluble, organic-soluble, and volatile chemicals, are found in Ganoderma. The main components are polysaccharides, adenosine, and terpenoids, each of which has exceptional therapeutic properties. This article explains the synthesis of Ag NPs by Ganoderma lucidum and tests the antibacterial effectiveness for use in biological applications. [ABSTRACT FROM AUTHOR]

The development of an effective and eco-friendly silver nanoparticle (AgNPs) to abate the effect of abiotic stress is an important area of nano-biotechnology. This study aimed to study the priming effect of plant-based green-synthesized silver nanoparticles and melatonin on the physiological and biochemical activities of drought-stressed E. uniflora. Sterilized seeds of E. uniflora were primed with 0.06 mg/l of ML-AgNPs, 0.06 mg/l of melatonin, and a nano-silver formulation of melatonin (1:1). Primed seeds were planted and subjected to 7 days under drought stress. The ML-AgNPs enhanced germination percentage, speed and vigor, and shoot elongation and induced the production of APx, CAT, and proline dehydrogenase (100% increases). Melatonin improved the activities of APx and CAT, total protein, accumulation of proline, and proline dehydrogenase (200% increases) and stabilized MDA content. Meanwhile, silver nano-formulation of melatonin increased leaves proliferation of leaves and production of APx, GPx, SOD, and CAT. Accumulation of proline and 100% upregulation of proline dehydrogenase osmo-regulated the effects of the drought, reduced MDA contents, and stabilized the excessive production of H2O2 and O2−. The ML-AgNO3 showed an efficient delivery system of melatonin into the plant under drought stress. As a result, our research shows that melatonin in silver nano-formulation (1:1) is a useful biostimulant against drought stress. [ABSTRACT FROM AUTHOR]

Since the late 2010-s and early 2020s, people around the world have not only encountered the pandemic crisis, but also in some places, they have had to deal with serious levels of air pollution. Personal protective equipment is essential to protect from microorganisms or fine particulate matter. Consequently, this study aimed to develop a silk face covering that could meet the international requirements with the addition of having an antibacterial property. The developed silk face covering consisted of three layers; the outer layer was water-repellent mulberry silk, the inner layer was oil-repellent eri silk, while the middle layer was cotton fabric coated with biosynthesized silver nanoparticles from mangosteen peels mixed with Andrographis paniculata extract. A biodegradable bacterial cellulose filter made of nata de coco waste was also prepared to improve filtration efficiency. It was found that the silver nanoparticles extracted from mangosteen peel and Andrographis paniculata inhibited S. aureus and E. coli by more than 99.9%, even after 20 washing cycles. The performance properties of the silk barrier face covering met Level I of the ASTM F3502-2021 standard, as well as being comfortable for public use. [ABSTRACT FROM AUTHOR]

The effective control of pathogenic bacteria is crucial in the restoration of periodontal tissue affected by periodontitis. Guided tissue regeneration (GTR) membranes are commonly used to aid in the repair of periodontal defects. Therefore, there is a clear advantage in developing antibacterial periodontal membranes that can effectively eliminate infections and promote tissue regeneration. This study aimed to create a collagen membrane with optimal content of silver nanoparticles (AgNPs) for effective antibacterial properties and minimal toxicity to mammalian cells. Ascorbic acid-reduced AgNPs were incorporated into collagen at the ratio of 0.5%, 1%, 2%, and 3% (based on total dry weight). Collagen/AgNPs hydrogels were compressed and freeze-dried to form membranes and then were characterized. Antibacterial activity was tested against Fusobacterium nucleatum and Enterococcus faecalis, and membrane cytocompatibility was accomplished on human gingival fibroblasts. Membranes with 2% and 3% AgNPs exhibited significant antibacterial activity, while 1% showed minimal activity and 0.5% and 0% showed none. HGF cells on the 3% AgNPs membrane had poor viability, proliferation, and adhesion, but 0%, 0.5%, 1%, and 2% AgNPs membranes showed desirable cellular behavior. In conclusion, the collagen membrane with 2% AgNPs demonstrated both antibacterial capacity and excellent cytocompatibility, making it a promising choice for periodontal treatments, especially in GTR approaches. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a causative agent of nosocomial infections and its antibiotic-resistant strains give cause for concern. Solutions are being explored to improve treatment for these infections, including repositioning drugs such as statins and using nanoparticles with antimicrobial properties. This study evaluated the antimicrobial effects of simvastatin (SIM) and biologically synthesized silver nanoparticles (bio-AgNPs) in isolate form and in combination using assays of minimum inhibitory concentration (MIC), an in vitro biofilm model, and the association of antimicrobials against clinical strains of S. aureus. Bio-AgNPs showed a 53.8 ± 1.23 nm mean diameter and standard deviation, a 0.23 polydispersity index, and a −25.66 ± 2.19 mV mean potential and standard deviation. Transmission electron microscopy confirmed the formation of nanoparticles, and the presence of Ag0 and AgCl. S. aureus strains were sensitive to bio-AgNPs and SIM, showing 31.88–187.5 and 74.66–149.32 μM concentrations, respectively. The association assay showed 2.0 fractional inhibitory concentration indices (i.e., indifferent for clinical strains) and 0.32 values for the standard ATCC 29213 strain (synergy). Biofilm inhibition assays with isolated SIM and bio-AgNPs showed decreased biofilm formation 4× to ⅛ MICs concentrations, showing no synergism in association. These findings evince that simvastatin and bio-AgNPs at subinhibitory concentrations can serve as antimicrobial agents against S. aureus biofilm. [ABSTRACT FROM AUTHOR]

Leishmania is the primary cause of a significant public health problem known as leishmaniasis in Iran. Pentavalent antimonial chemicals are commonly used for the treatment of leishmaniasis. However, these drugs exhibit a number of adverse effects, including drug resistance, lack of specificity, poor responsiveness, toxic effects, inconvenient injections, tissue damage, and high cost. The present study aimed to prepare and evaluate the efficacy of green-synthesized silver nanoparticles (Ag-NPs) against Leishmania infantum and Leishmania tropica in vitro. The 2, 5-Diphenyl Tetrazolium Bromide (MTT) assay was used to assess the toxicity of Ag-NPs derived from ginger extract on macrophage cells. The apoptotic potential of promastigotes caused by Ag-NPs was evaluated using the flow cytometry method. According to our findings, the proliferation of L. infantum and L. tropica, promastigotes are significantly decreased by increasing doses of NPs. The most effective doses of nanoparticle were 80 and 40 ppm after 48 and 72 hours of incubation, respectively, while doses of 0.312 and 0.156 ppm after 24 and 48 hours of incubation had the least effect on the growth and activity of L. infantum and L. tropica promastigotes. For the promastigotes of L. infantum and L. tropica, the flow cytometry test revealed that Ag-NPs-induced programmed cell death in promastigotes of L. infantum and L. tropica demonstrated 67.1% and 41.9% of apoptosis, respectively. The half-maximal inhibitory concentration for NPs against L. infantum and L. tropica were 4.54 and 4.22 ppm, respectively, based on the MTT assay. The higher concentrations of NPs (e.g., 80 ppm) led to more lethality of promastigote. In conclusion, Ag-NPs exhibited good in vitro anti-leishmanial activity against L. infantum and L. tropica promastigotes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cerebral ischemia and reperfusion are related to various situations like injuries after various traumas, oxidative stress, increased calcium ion, capillary hypoperfusion, microvascular hyperpermeability, leukocyte infiltration, and blood–brain barrier disruption. An antidepressant Agomelatine which is a melatonin receptor (MT1/MT2) agonist and serotonin receptor (5‐HT2C) antagonist has been reported by studies to have antioxidant and anti‐inflammatory effects. In our study, we aimed to detect the effects of citrate‐coated silver nanoparticle‐loaded agomelatine application on neurodegeneration, endoplasmic reticulum stress, autophagic and apoptotic cell death, inflammation, and P2X7R expression in the cerebral ischemia–reperfusion model to facilitate the passage of blood–brain barrier. Forty two Sprague–Dawley rats in total were divided into six equal groups (n:7) and applications were performed. Acute cerebral injury in the ischemia–reperfusion model was created 2 h after internal carotid artery ligation in rats and then at the 2nd hour of reperfusion citrate‐coated silver nanoparticles loaded with Agomelatine were applied. Twenty four hours later, neurologic analysis on animals in experimental groups was performed, animals were decapitated and GSH, GPx, SOD, CAT, MDA, IL‐1β, and TNF‐α parameters were examined after taking blood and the cerebral tissue samples. As a result, it was determined that ischemia–reperfusion caused endoplasmic reticulum stress in the cerebral tissues and thus caused cellular injury. [ABSTRACT FROM AUTHOR]

Silver nanoparticles on a glass substrate are experimentally investigated by aperture scanning near-field optical microscopy (a-SNOM). To understand the experimental results, finite-element-method simulations are performed building a theoretical model of the a-SNOM geometry. We systematically vary parameters like aperture size, aluminum-coating thickness, tip cone angle, and tip-surface distance and discuss their influence on the near-field enhancement. All these investigations are performed comparatively for constant-height and constant-gap scanning modes. In the end, we establish a reliable and stable optical model for simulating a-SNOM measurements, which is capable of reproducing trends observed in experimental data. [ABSTRACT FROM AUTHOR]

In this study, we biosynthesized the stable silver nanoparticles (AgNPs) from Momordica cymbalaria leaves to evaluate their antioxidant, antibacterial, cytotoxic, and photocatalytic properties. Initially, we screened the bioactive compounds from M. cymbalaria extract using GC-MS. The biosynthesis of Mc-AgNPs was confirmed using instruments, such as UV-visible spectroscopy FT-IR, XRD, SEM with EDX, and HR-TEM analyses. The UV-visible spectrum indicated absorbance at 425 nm. The crystallite size of the M. cymbalaria-stabilized nanoparticles was determined to be 20.14 nm. The morphology and size of the synthesized Mc-AgNPs were confirmed via SEM-EDX and HR-TEM analyses, with a size range from 16 to 22 nm. The synthesized Mc-AgNPs exhibited a photocatalytic yield of 60%. The biosynthesized Mc-AgNPs demonstrated strong antioxidant properties and prominent antibacterial activity against human pathogenic bacteria. The cytotoxicity study revealed that Mc-AgNPs were effective against MCF-7 cells in a dose-dependent manner. The recognized bioactivities confirm that the synthesized Mc-AgNPs act as effective catalysts in oxidation and serve as potent antioxidant, anticancer, and antibacterial agents. [ABSTRACT FROM AUTHOR]

Bioactive and biocompatible BC/AgNP composite films were synthesized by loading silver nanoparticle (AgNP) into bacterial cellulose (BC) fibrils. Physicochemical analyses (FTIR, TGA-DSC, SEM-EDS, TEM, XRD) and mechanical tests were performed on the synthesized BC fibril and BC/AgNP composite films. Young's Modulus, Tensile strength, Elongation at break, Compressive strength and Stiffness of (45% moisture) BC/AgNP composite films were found to be 253.2 ± 2.01 MPa, 13.7 ± 1.40 MPa, 21.4 ± 1.67%, 47.17 ± 8.98 MPa, 1.05 ± 2.32 GPa and 519.88 ± 81.51 (Units), respectively. Moreover, the high-water retention capacity of BC fibril structures was supported by the contact angles and swelling profiles observed in BC/AgNP composite structures. Further, the bioadhesion performance of BC/AgNP composite films was evaluated ex vivo on chicken skin and it was observed that the presence of AgNP played an active role in the adhesion behavior of the composite films. It was also observed that the synthesized BC/AgNP composite films exhibited bactericidal behavior against pathogens (Staphylococcus aureus and Pseudomonas aeruginosa) and had a high bactericidal effect. Biocompatibility tests of the composite films were evaluated by using L929 mouse fibroblast cells. The cell nucleus wall staining (Mitored and Dio6) and fluorescence visualization studies were performed to investigate the biocompatibility behavior of BC/AgNP composite films. The results showed that BC/AgNP composite films did not any cytotoxic effect and allowed epidermal cells to adhere and grow. Overall, obtained results showed that the synthesized biocompatible BC/AgNP composite films are suitable to be used as wound dressings in tissue engineering applications and may be used as a bioactive material that can reduce inflammation in skin barriers and promote wound healing. [Display omitted] • Bacterial cellulose was produced by bacteria (Gluconacetobacter hansenii , ATCC 23769) incubated under a static condition. • SEM-EDS, FTIR, TGA and XRD showed the incorporation of silver nanoparticles. • Bacterial cellulose-silver nanoparticle composite film exhibited bioadhesive behaviour. • Bacterial cellulose-silver nanoparticle composite film exhibited good antibacterial properties. • Bacterial cellulose-silver nanoparticle composite film did not exhibit cytotoxic behaviour. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) synthesized using tartaric acid as a capping agent have a great impact on the reaction kinetics and contribute significantly to the stability of AgNPs. The protective layer formed by tartaric acid is an important factor that protects the silver surface and reduces potential cytotoxicity problems. These attributes are critical for assessing the compatibility of AgNPs with biological systems and making them suitable for drug delivery applications. The aim of this research is to conduct a comprehensive study of the effect of tartaric acid concentration, sonication time and temperature on the formation of silver nanoparticles. Using Response Surface Methodology (RSM) with Face-Centered Central Composite Design (FCCD), the optimization process identifies the most favorable synthesis conditions. UV-Vis spectrum regression analysis shows that AgNPs stabilized with tartaric acid are more stable than AgNPs without tartaric acid. This highlights the increased stability that tartaric acid provides in AgNP ssssynthesis. Particle size distribution analysis showed a multimodal distribution for AgNPs with tartaric acid and showed the smallest size peak with an average size of 20.53 nm. The second peak with increasing intensity shows a dominant average size of 108.8 nm accompanied by one standard deviation of 4.225 nm and a zeta potential of -11.08 mV. In contrast, AgNPs synthesized with polyvinylpyrrolidone (PVP) showed a unimodal particle distribution with an average particle size of 81.62 nm and a zeta potential of -2.96 mV. The more negative zeta potential of AgNP-tartaric acid indicates its increased stability. Evaluation of antibacterial activity showed that AgNPs stabilized with tartaric acid showed better performance against E. coli and B. subtilis bacteria compared with AgNPs-PVP. In summary, this study highlights the potential of tartaric acid in AgNP synthesis and suggests an avenue for the development of stable AgNPs with versatile applications. [ABSTRACT FROM AUTHOR]

Polymer-based membranes represent an irreplaceable group of materials that can be applied in a wide range of key industrial areas, from packaging to high-end technologies. Increased selectivity to transport properties or the possibility of controlling membrane permeability by external stimuli represents a key issue in current material research. In this work, we present an unconventional approach with the introduction of silver nanoparticles (AgNPs) into membrane pores, by immobilising them onto the surface of polyethyleneterephthalate (PET) foil with subsequent physical modification by means of laser and plasma radiation prior to membrane preparation. Our results showed that the surface characteristics of AgNP-decorated PET (surface morphology, AgNP content, and depth profile) affected the distribution and concentration of AgNPs in subsequent ion-track membranes. We believe that the presented approach affecting the redistribution of AgNPs in the polymer volume may open up new possibilities for the preparation of metal nanoparticle-filled polymeric membranes. The presence of AgNPs on the pore walls can facilitate the grafting of stimuli-responsive molecules onto these active sites and may contribute to the development of intelligent membranes with controllable transport properties. [ABSTRACT FROM AUTHOR]

This work aims to enhance the dye-removal performance of prepared poly(acrylic acid-co-acrylamide)-modified, deproteinized, natural rubber ((PAA-co-PAM)-DPNR) through incorporation with silver nanoparticles/titanium dioxide. The (PAA-co-PAM)-DPNR was prepared by emulsion-graft copolymerization with a grafting efficiency of 10.20 ± 2.33 to 54.26 ± 1.55%. The composites based on (PAA-co-PAM)-DPNR comprising silver nanoparticles and titanium dioxide ((PAA-co-PAM)-DPNR/Ag-TiO2) were then prepared by latex compounding using the fixed concentration of AgNO3 (0.5 phr) and varying concentrations of TiO2 at 1.0, 2.5, and 5.0 phr. The formation of silver nanoparticles was obtained by heat and applied pressure. The composites had a porous morphology as they allowed water to diffuse in their structure, allowing the high specific area to interact with dye molecules. The incorporation of silver nanoparticles/titanium dioxide improved the compressive modulus from 1.015 ± 0.062 to 2.283 ± 0.043 KPa. The (PAA-co-PAM)-DPNR/Ag-TiO2 composite with 5.0 phr of TiO2 had a maximum adsorption capacity of 206.42 mg/g, which increased by 2.02-fold compared to (PAA-co-PAM)-DPNR. The behavior of dye removal was assessed with the pseudo-second-order kinetic model and Langmuir isotherm adsorption model. These composites can maintain their removal efficiency above 90% for up to five cycles. Thus, these composites could have the potential for dye-removal applications. [ABSTRACT FROM AUTHOR]

Tephrosia purpurea silver nanoparticles (TP‐AgNPs) were synthesized with water‐based leaf extract of the plant T. purpurea. UV–Vis characterization had shown the maximum absorbance at 436 nm. The surface morphology was examined via electron microscopy (FE‐SEM) analysis (average size: ~100 nm, shape: spherical). The zeta potential (ZP) of TP‐AgNPs revealed values of −41.72 mV suggesting appropriate physical stability. Besides, an X‐ray crystallography (XRD) study had shown the crystalline size of 20 nm approximately having 2θ values of 32°, 38°, 44°, 64°, and 77° for the silver crystals. The energy dispersive (EDAX) study manifests the absorption peak at 2.983 keV for TP‐AgNPs. Infrared spectroscopy analysis (Fourier‐transform infrared spectroscopy) indicated the presence of alcoholic as well as aromatic groups in the extract that took part in the stability and silver reduction mechanisms. Biologically, TP‐AgNPs had shown prominent anti‐oxidant activities against 2,2‐diphenyl‐1‐picrylhydrazyl radicals (IC50 50 μg/mL) and H2O2 radicals (IC50 106 μg/mL). It had also inhibited the proliferation of breast cell lines (MCF 7) showing total growth inhibition (TGI) at 8.2 μg/mL with the LC50 of 44 μg/mL for TP‐AgNPs. Further, hemolysis analysis revealed that TP‐AgNPs are non‐toxic to human erythrocyte cells (RBCs) as they do not cause the breakdown of RBCs. Thus, TP‐AgNPs were found to be an effective agent to be studied further for chemotherapeutic mechanisms. [ABSTRACT FROM AUTHOR]

The use of silver nanoparticles (Ag-NPs) in different fields such as agriculture, medicine, and environment has recently increased. As a result, studies on their synthesis and applications have gained attention. In the present study, the synthesis of Ag-NPs using cheap, renewable, and environmentally friendly phytochemicals extracted from Vachellia xanthophloea leaves is reported. Additionally, potential uses of the nanoparticles against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria and for sensing of mercury ions from aqueous solutions were investigated. The findings showed that the formation of nanoparticles was associated with a color change from green to brown with a UV–Vis maximal absorbance peak at 420 nm due to surface plasmon resonance on Ag-NPs. The synthesized Ag-NPs showed effective antibacterial effects against both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria. The antibacterial effectiveness as indicated by the minimum inhibitory concentration (MIC) was higher for Staphylococcus aureus (0.04 mg/mL) compared to E. coli (0.33 mg/mL). Similarly, the minimum bactericidal concentration (MBC) values were 0.04 and 0.66 mg/mL for S. aureus and E. coli, respectively. The nanoparticles were also sensitive to metal ions (Hg2+, Ba2+, Mg2+, Zn2+, Cu2+, Ni2+, Co2+, and Fe2+) and showed a remarkable selectivity to mercury. The potential use of the nanoparticles for sensing of mercury ions from real water samples of ground and tap waters produced satisfactory results. The limit of detection (LOD) and limit of quantification (LQD) for sensing of Hg2+ were determined to be 22.2 µM and 73.9 µM, respectively. The findings from the current study indicate that Ag-NPs prepared using Vachellia xanthophloea leaves aqueous extract could serve as effective an antibacterial agent and a sensor of mercury ions for aqueous samples. [ABSTRACT FROM AUTHOR]

Discovery of antibiotics is regarded as one of the critical moments in the history of medicine; however, irrational use caused the emergence of a phenomenon known as drug resistance. Once considered benign, Acinetobacter baumannii (A. baumannii) evolved to become a challenging pathogen threatening the current antibiotic era. In 2017, WHO appointed A. baumannii as the most critical pathogen towards which the development of novel antibiotics is keenly required. The current study intends to explore the silver nanoparticles (AgNPs) role in the weakening of virulence and biofilm through reducing the expression of outer membrane protein-A (OmpA), biofilm-associated protein (Bap), Acinetobacter baumannii autoinducer-I (abaI) and Acinetobacter baumannii receptor (abaR) genes in the multi-drug resistant (MDR) A. baumannii. All bacterial isolates were capable to form biofilm and exhibited high resistance levels to the antibiotics used including (ampicillin/sulbactam, ceftazidime, tobramycin, amikacin, gentamicin, levofloxacin, imipenem, ciprofloxacin, meropenem, piperacillin/tazobactam, cefepime, ceftriaxone, doxycycline, and trimethoprim/sulfamethoxazole). AgNPs were biologically synthesized by Pseudomonas aeruginosa (P. aeruginosa) (PA-AgNP) and characterized via FTIR, UV-vis, EDX, XRD, and SEM. Results of characterization tools supported the successful formation of crystalline AgNPs. Minimum-inhibitory concentrations of the harvested AgNPs were determined to study their antibiofilm and quorum quenching potential at subinhibitory concentrations (SIC). RT PCR was utilized to estimate the influence of PA-AgNPs on the quorum sensing (QS) and biofilm at level of gene expression. Exposure of the tested isolates to PA-AgNP at SIC values decreased their biofilm fabrication capacity and significantly downregulated candidate genes expression. The results show that P. aeruginosa can be used to bio-fabricate AgNPs capable of interrupting bacterial-growth and biofilm progress in the MDR A. baumannii through the downregulation of QS and biofilm-associated genes. [ABSTRACT FROM AUTHOR]

In this research article we report the potentials of chitin-based silver nanoparticles (chitin AgNPs) derived from Indian mimic goatfish (Mulloidichthys ayliffe) scales as an effective food preservation agent. The study comprehensively presents the multifaceted attributes of chitin AgNPs, including their synthesis, characterization, and antimicrobial properties. Chitin yield from M. ayliffe scales and three-spot swimming crab (P. sanguinolentus) exoskeleton was determined, with the insoluble content quantified. FTIR analysis unveiled distinct absorption peaks for chitin, and scanning electron microscopy revealed the ultrastructure of chitin from both the sources. Using UV–visible spectroscopy, the biosynthesis of AgNPs was accomplished and characterized, with the color shift of the solution serving as proof of a successful synthesis. UV–vis spectra provided insights into nanoparticle size and shape. SEM micrographs exhibited spherical particle morphology, while FTIR spectra indicated amino group interactions contributing to AgNP stabilization. The antimicrobial potential of chitin AgNPs was assessed against the food pathogen, Vibrio spp. Chitin films displayed significant antimicrobial activity, particularly AgNP-synthesized chitin from M. ayliffe scales, demonstrated the highest Vibrio spp. inhibition activity. Furthermore, chitin AgNPs were incorporated into the common chili, Capsicum annuum and the tomato, Solanum lycopersicum to extend their shelf life at room temperature. This study reveals the efficacy of chitin AgNPs from M. ayliffe scales as potent agents for food preservation, offering insights into their physical, mechanical, and antimicrobial attributes. The application of chitin AgNPs to perishable food items highlights their potential in enhancing shelf life and quality, opening innovative avenues for sustainable food preservation. [ABSTRACT FROM AUTHOR]