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The biosynthesis of silver nanoparticles (AgNPs) using an aqueous extract of an agroindustrial residue of the tequila industry [i.e. leaves of Agave tequilana Weber var. azul (AT)], and silver nitrate or silver acetate as precursor salts is reported. The presence of AgNPs was confirmed by color change, scanning electron microscopy, ultraviolet visible spectroscopy and X-ray diffraction. AgNPs were tested against clinically important bacteria. The effect of extract concentration and the reaction temperature was investigated. Results revealed that, the concentration of AgNPs increases as temperature and extract concentration increase. AgNPs were found to be mainly spherical shaped and showed antibacterial activity against Staphylococcus aureus , Escherichia coli and Pseudomonas aeruginosa . Results demonstrate the possibility of using a natural extract obtained from an abundant agroindustrial residue for the sustainable synthesis of AgNPs. [ABSTRACT FROM AUTHOR]

We have demonstrated a one pot green protocol for the synthesis of highly monodispersed silver nanoparticles using leaves of Salvadora persica plant. When the leaf extract of Salvadora persica plant reacted with silver nitrate (AgNO 3 ) solution it resulted in the synthesis of highly monodispersed silver nanoparticles with an average size of 3 nm. These nanoparticles were then completely characterized by UV–Visible spectroscopy, Transmission Electron Microscopy, Energy Dispersive Analysis of X-Rays, X-ray diffraction analysis and Fourier Transform Infrared analysis. [ABSTRACT FROM AUTHOR]

Green synthesis of silver nanoparticles (AgNPs) has gained widespread interest as the alternative method to use natural, non-toxic substances to facilitate the formation of AgNPs. This work reported on the alternative source of reducing and stabilizing agents from tissue extract of weaver ant ( Oecophylla smaragdina ) larvae. The formation of AgNPs in the reaction containing silver nitrate, the tissue extract, and glucose at 60 °C was indicated by the surface plasmon resonance at 428 nm. Transmission electron microscopy images revealed spherical AgNPs with the average diameter of 67.4 nm. The synthesized AgNPs exhibited potent antibacterial activity against both Staphylococcus aureus and Escherichia coli with the minimum bactericidal concentrations equally at 16 μg/mL. [ABSTRACT FROM AUTHOR]

This paper presents a facile, and ecofriendly method to prepare colloidal silver nanoparticles (AgNPs) at room temperature using bulk silver bars, bi-distilled water, trisodium citrate, and a direct-current voltage source. AgNP formation was confirmed and characterized by ultraviolet–visible spectroscopy, transmission electron microscopy and X-ray diffraction. Their antibacterial activity was examined by disc diffusion and minimum inhibitory concentration (MIC) techniques against three bacterial strains, including the Gram-positive bacteria Staphylococcus aureus and the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa . Results showed that the size of AgNPs formed was about 19.7±4.3 nm with nearly spherical shape and high purity. The antibacterial activity of as-prepared AgNPs was determined through zones of inhibition against the growth of three bacterial strains on agar. MIC analysis showed that S. aureus had resistance to AgNPs that was about 2–3 times higher than those of E. coli and P. aeruginosa , and that resistance ability depended on the bacterial concentrations inoculated. This work revealed the effective method of synthesizing a large quantity of colloidal AgNPs with high antibacterial effectiveness and potential application in different fields. [ABSTRACT FROM AUTHOR]

Biological entity is gaining significant prominence in green synthesis of silver nanoparticles as a result of their potential applications in nanomedicine and material engineering. Herein, we have reported the green synthesis of Artocarpus altilis silver nanoparticles (BAgNPs) using aqueous leaf extract of Artocarpus altilis . Synthesized colloidal BAgNPs were confirmed spectrophotometrically at 432 nm and the various reaction conditions were optimized. The SEM, TEM and DLS analysis confirmed that the average particle size of BAgNPs was 34 nm, 38 nm, and 162.3 d.nm, respectively. Nature and presence of silver were confirmed by XRD and EDX. Further, FT-IR spectra of the synthesized BAgNPs authorized the presence of phyto constituents as capping agent. The BAgNPs showed moderate antimicrobial and antioxidant activities. The present study revealed the safer use of eco-friendly green synthesized BAgNPs in near future in the field of biomedicine, water treatment or purification, and nanobiotechnology. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) were synthesized in low cost skim natural rubber latex by adding silver nitrate as a source of silver ions. Left-over ammonia in latex was believed to form a complex with silver ions before reacting with the reducing agents which were glucose and other organic compounds in latex. Moreover, protein in latex could also control the growth of the particles by acting as a stabilizing agent. Many factors, which include ammonia content, d -glucose content and BSA protein content, were studied to clarify their effects in the synthesis. The emergence of AgNPs was checked with UV–visible spectrometer and electrical conductivity meter. Transmission electron microscope (TEM) was applied to study the particle morphology. The results showed that UV absorbance (ABS) and conductivity of the reacting suspension increased when ammonia content and d -glucose content increased, implying an increasing number or growth of particles. In contrast, ABS and conductivity decreased with increasing BSA content, showing that smaller particles were formed. The TEM images confirmed that the size of AgNPs in the none-added sample was 6–26 nm. The synthesized AgNPs could inhibit the growth of Escherichia coli and Staphylococcus aureus . [ABSTRACT FROM AUTHOR]

The present study was aimed at the biosynthesis of silver nanoparticles (AgNPs) using aqueous extract of Clerodendron serratum (AECS) leaves and testing their potential in vitro anticancer activity using Ehrlich ascites carcinoma (EAC) cell lines. This medicinal plant was found to be rich in polyphenol glycosides and two compounds-baicalein and quercetin 3-O-β- d -glucoside was isolated from the extract. The biologically synthesized AgNPs were characterized using UV–vis spectrophotometry, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD). The antiproliferative ability of the AgNPs was evaluated using cell viability and MTT assays and the results showed that biosynthesized AgNPs possesses significant in vitro antiproliferative activity. [ABSTRACT FROM AUTHOR]

The present study focuses on a simple, low-cost and rapid bio-reduction of silver nitrate to silver nanoparticles (AgNPs) using the hot water extract of fresh basidiocarps of Pleurotus cornucopiae var. citrinopileatus. P. cornucopiae is an edible mushroom with medicinal properties. The UV–visible (UV–vis) spectra showed intense absorption peaks at 400 to 500 nm, which are typical absorption bands of spherical AgNPs. Fourier transform infra-red (FT-IR) spectra confirmed the involvement of various functional groups present in the biomolecules for reduction and capping of AgNPs. The spherical shaped morphology and <100 nm particle size of the sample AgNPs was confirmed by field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). Energy dispersive X-ray analysis (EDX) illustrated that the AgNPs were crystalline in nature. Mycosynthesized AgNPs significantly ( p <0.05) inhibited the growth of all Candida species tested. [ABSTRACT FROM AUTHOR]

Abstract: Ag nanoparticles (AgNP) with an average size of 12nm are successfully decorated on the reduced graphene oxide (rGO) sheets through a simple one-pot hydrothermal method using gallic acid as the reducing agent. This AgNP/rGO hybrid has been successfully applied in the catalytic performance toward the reduction of H2O2. The nonenzymatic sensor demonstrates a linear relationship in a wide concentration range of 0.05–5mM (R=0.999), and a high sensitivity of 255μAcm−2 mM−1 to the detection of H2O2. [Copyright &y& Elsevier]

Abstract: A completely green and large scale controlled synthesis of stable, smaller sized (<5nm) and monodispersed quasi spherical starch-capped silver nanoparticles (Ag NPs) using maltose as the reducing agent without any complexant or accelerator is presented. High concentration of the reducing saccharides produced via hydrolysis of maltose and partial hydrolysis of starch as the reaction time increases controls the particle diameter within the smaller size range. [Copyright &y& Elsevier]

Abstract: Biologically dependable processes for the green synthesis of silver nanoparticles (Ag NPs) were developed in nanoscience and nanotechnology. In this present paper, green synthesis of Ag NPs was performed from aqueous silver nitrate using the fresh Ixora coccinea L., leaves extract. The formation of Ag NPs was observed by the change of color from colorless to dark brown by the addition of silver nitrate into leaves extract. The synthesized Ag NPs were characterized by UV–vis, FTIR and XRD analyses. Further, the size and shapes of Ag NPs were identified by field emission scanning electron microscope (FESEM) technique to obtain particle sizes in the range from 13 to 57nm. [Copyright &y& Elsevier]