Journal of Nanomedicine & Nanotechnology

Abstract

Dioscorea oppositifolia Mediated Synthesis of Gold and Silver Nanoparticles with Catalytic Activity

Sougata Ghosh, Sonal P Gurav, Ashwini N Harke, Maliyackal Jini Chacko, Komal A Joshi, Aarti Dhepe, Chaitanya Charolkar, Vaishali Shinde, Rohini Kitture, Rohini Kitture, Vijay Singh Parihar, Kaushik Banerjee, Narayan Kamble, Jayesh Bellare and Balu A Chopade

Biological approaches for synthesis of nanoparticles have gained prime attention in the recent decade as they not only involve lesser time and energy consumption compared to physical and chemical methods but also rapid, efficient and nontoxic. Medicinal plants with diverse phytochemistry have been considered as most promising for development and design of novel routes to synthesize metal nanoparticles. Herein, we report for the first time the synthesis of gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) using Dioscorea oppositifolia tuber extract (DOTE). The synthesis process was complete within 5 h as observed in UV-visible spectroscopy. High resolution transmission electron microscopy revealed that the bioreduced AuNPs were anisotropic exhibiting exotic shaped like nanohexagons, pentagons and blunt ended triangles. Spherical AuNPs ranging from 30 to 60 nm were also spotted. Similarly, distinctly spherical AgNPs without any agglomeration were observed with a size ranging between 17 to 25 nm. Both AuNPs and AgNPs were characterized using various techniques like energy dispersive spectroscopy, X-ray diffraction, dynamic light scattering and fourier transform infrared spectroscopy. Phytochemical analysis employing biochemical tests and GCMS/MS revealed the presence of phenolics, flavonoids, starch, ascorbic acid and citric acid that may help not only in reduction but also in stabilization of the bioreduced nanoparticles. AuNPs and AgNPs synthesized by DOTE exhibited efficient catalytic activity towards reduction of 4-nitrophenol to 4-aminophenol by NaBH4 with a pseudo-first order rate kinetics.