Biosynthesis and characterization of gold nanoparticles using plant extracts

Here is an effort to present the rapid, reliable and eco-friendly synthesis of gold nanoparticles (GNPs) by green biogenic approach. The method uses aqueous extracts of Betel leaf, Hibiscus leaf, Lantana camara and nuts of bitter guard as reducing as well as stabilizing agent. Gold nanoparticles were synthesized by thermal reduction (microwave irradiation) of chloroauric acid (HAuCl4) using aqueous extracts of plant materials mentioned above. The formation of gold nanoparticles was confirmed by using UV-Visible spectra. Gaussian curves with absorbance peaks were obtained between 500 nm to 600 nm which confirms to similar previous investigations. Bioreduction of 0.5 mM and 1mM HAuCl₄ by varying gold salt and extract ratio were investigated. Approximate sizes of synthesized GNPs were predicted using Mie Plot software according to which they vary in the range of 26-63nm.