Biosynthesis of silver nanoparticle from leaf extract of Desmodium gangeticum (L.) DC. and its biomedical potential

Abstract

An aqueous leaf extract of Desmodium gangeticum was employed to synthesize silver nano particles. Rapid formation of stable silver nanoparticles were observed on exposure of the aqueous leaf extract with solution of silver nitrate. The silver nanoparticles were characterized by UV-visible spectroscopy, scanning electron microscopy, energy dispersive X-ray analysis and transmission electron microscopy (TEM), and Fourier Transform Infra-Red spectroscopy (FTIR) UV-visible spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), transmission electron microscopy (TEM), and Fourier Transform Infra-Red spectroscopy (FTIR). UV-visible spectrum of the aqueous medium peaked at 450 nm corresponding to the plasmon absorbance of silver nanoparticles. SEM analysis revealed the spherical shape of the particles with sizes ranging from 18 to 39 nm and the EDAX spectrum confirmed the presence of silver along with other elements in the plant metabolite. Further, these biologically synthesized nanoparticles were found to be highly toxic against pathogenic bacteria Escherichia coli, thus implying significance of the present study in production of biomedical products. (C) 2013 Elsevier B.V. All rights reserved.