Green synthesis of silver nanoparticles using aqueous solution of Ficus benghalensis leaf extract and characterization of their antibacterial activity

Abstract

The present study reports an environmentally friendly and rapid method for synthesis of silver nanoparticles. Although several articles have been reported for the synthesis of silver nanoparticles from plant extract, here we have developed a green synthetic method for silver nanoparticles using Ficus benghalensis leaf extract which acts as a reducing and capping agent. It was observed that use of Ficus benghalensis leaf extract makes a fast and convenient method for the synthesis of silver nanoparticles and can reduce silver ions into silver nanoparticles within 5 min of reaction time without using any harsh conditions. Silver nanoparticles so prepared were characterized by using UV–visible spectroscopy, transmission electron microscope-energy dispersive spectra (TEM-EDS) and X-ray diffraction (XRD). Further, these nanoparticles show effective antibacterial activity toward E.coli MTCC1302 due to high surface to volume ratio.

Introduction

In this era, nanotechnology is one of the most interesting area which is used to describe the creation and utilization of materials with structural features between those of atoms and bulk materials with at least one dimension in the nano range. Synthesis of metal nanoparticles is enormous and expanding area due to their potential applicability in various areas such as electronics, chemistry, energy, and medicine development. Nanoparticles exhibit new or improved properties depending upon their size, morphology and distribution [1], [2]. To fulfill the growing need of environmental friendly nanoparticles, researchers are using microorganisms for the synthesis of various metal nanoparticles [3], [4], [5], [6], [7], [8], [9], [10]. But nowadays, plant extract has been used as reducing and capping agent for the synthesis of nanoparticles which could be advantageous over microbial synthesis because there is no need of the elaborated process of culturing and maintaining the cell. Plant leaf extract of tamarind [11], Syzygium cumini [12], onion [13], basil [14] and banana peel [15] had been used for synthesis of gold and silver nanoparticles, which lead to formation of pure metallic nanoparticles of silver and gold and can be used directly. Further, the antibacterial activity of synthesized silver nanoparticles showed effective inhibitory activity against water borne pathogens [16]. These nanoparticles have effective antibacterial properties and very less amount is required for same antimicrobial activity that would have been produced by large amount of bulk counterparts.

In this study, we have synthesized silver nanoparticles with the help of Ficus benghalensis leaf extract by reduction of Ag⁺ to Ag⁰ from silver nitrate solution and investigated the antibacterial activity of nanoparticles against E.coli MTCC 1302.