Bacterial synthesis of silver nanoparticle

Abstract

There are numerous reports on the synthesis of silver nanoparticles by using chemical and physical methods, but the development of reliable technology to produce nanoparticles is important. Biological synthesis process is regarded as safe and biocompatible method with low cost and minimum time. In this study, synthesis of silver nanoparticles is done by Gram-positive bacterial strain. The bacterial strains were isolated from soil samples. A bacterial strain resistant to silver nitrate was selected for the synthesis of AgNPs. The biomass of bacterial strain was added to the reaction solution containing 1mM of silver nitrate. After the color change, reaction solution was analyzed using UV–Vis spectrophotometer. It was found that the isolated bacteria have the potential to form silver nanoparticles intracellularly. This was confirmed by formation of brown colour and the visual observation and UV–Vis absorption at 430 nm. Microbial synthesis of metal nanoparticles can take place either intracellularly or extracellularly. The present study showed ecofriendly production of silver nanoparticles using bacteria isolated from soil intracellularly. Although biological methods are regarded as safe and biocompatible, but the production of nanoparticles with controlled shape and size requires optimization.