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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]

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]

In this investigation, we report the formation of new 3-D aggregates consisting of Ag-Au nanoparticles obtained in aqueous solution by a facile method using Aloysia triphylla plant extract as a reducing and stabilizing agent. SEM and EDS analysis reveal that the dimensions of 3-D arrays are estimated to be about 2.5 µm wide, 0.5 µm thick, and 2 µm long. The 3-D geometric aggregates have strong microstructures that are similar to those of ordinary crystalline materials. The microstructures are close-packed with straight edges and facets but do not have grain boundaries. HRTEM images indicate that the 3-D arrays are a consequence of the nanoparticles aggregation inside an organic matrix and the presence of Au forming the BNPs. [ABSTRACT FROM AUTHOR]

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]

• A novel green synthesis method is employed for the synthesis of copper nanoparticles. • The average size of the synthesized Cu nanoparticles is in the range of 5–25 nm. • The obtained nanoparticles have shown good antibacterial activity against gram-positive and gram-negative bacteria. In the present report, for the first time aqueous extract of Curcuma longa powder is used for the synthesis of Copper nanoparticles (Cu NPs) using a simple and cost effective method. Morphology, size, crystallinity, composition and microstructure of the synthesized Cu Nps are studied. Size of the particles are in the range of 5–20 nm. In addition to the above, antibacterial activity of the obtained Cu NPs is tested for both gram-positive and gram-negative microorganisms. Zone of inhibition of Cu NPs for gram positive bacteria is more compared to gram negative bacteria. The current work on green synthesis of metallic nanoparticles can be considered as an alternative method to avoid the usage of hazardous compounds and bitter reaction conditions in the production of metal nanoparticles. The obtained Cu NPs with their distinctive structural properties and effective biological effects can be used in applications viz. antimicrobial, antifungal, anticancer activity. [ABSTRACT FROM AUTHOR]