An Insight into the Bacterial Biogenesis of Silver Nanoparticles, Industrial Production and Scale-up

Abstract

Silver nanoparticles have revolutionized the whole world with numerous applications in various fields including imaging to applications in medicine. For the synthesis of silver nanoparticles bottom approaches are very easy to perform and the size distribution can be easily maintained. Biologically synthesized silver nanoparticles are extremely stable without the use of any outside stabilizer, with an added advantage of synthesizing accurate and precise sized nanoparticles besides the use of nontoxic chemicals and stringent conditions. Other advantages include easy manipulations of the genetic material for enhanced synthesis of nanoparticles and maximum utilization of the raw materials as biological process usually goes to completion. Although several reports are available for the mechanism of synthesis of nanoparticles they report the intermediate steps and not the complete mechanism. So a screening over a genomic library constructed from those organisms synthesizing silver nanoparticles would give a better idea of the steps involved in the silver nanoparticle synthesis. Primarily silver nanoparticles are synthesized by AgNO₃ that aids the synthesis of silver nanoparticles at lower concentrations. But at higher concentrations it is highly toxic to the treated organism. This in fact makes the possibility of synthesis of silver nanoparticles to be a protective mechanism rather than a usual bioprocess. This requires a careful design of medium and optimization of the process for the maximum synthesis of nanoparticles. Response surface methodology can be practically applied to various process optimization processes and the final equation obtained can be used for the scaling up of the process.