Phytofabrication of silver nanoparticles by leaf extract of Datura metel: Hypothetical mechanism involved in synthesis

Development of environmental friendly procedures for the synthesis of metal nanoparticles through biological process is evolving into an important branch of nanobiotechnology. Generally, nanoparticles are synthesized by chemical and physical methods, which are not eco-friendly. In this paper, we report the fabrication of silver nanoparticles (NPs) and discuss the possible mechanism involved. Silver nanoparticles were rapidly synthesized by challenging silver ions with leaf extract of Datura metel. The reaction process is rapid, simple and easy to handle. The UV-Vis spectrum of aqueous medium containing silver nanoparticles showed peak at 420 nm corresponding to plasmon absorbance of silver nanoparticles. Transmission electron microscopic analysis of the silver nanoparticles indicated that they ranged in size from 16 to 40 nm and were assembled in solution into quasilinear superstructures. X-ray EDS analysis confirmed that Ag constituted the nanoparticles. It is assumed that alcoholic component (plastohydroquinone or plastrocohydroquinol) present in leaf extract is mainly responsible for reduction of silver ions thus indicating a possible mechanism of synthesis of silver nanoparticles by D. metel.