Journal of Pure and Applied MicrobiologyVol. 8 No. 6

An Alternative Method for Biological Production of Silver and Gold Nanoparticles

Behrooz Yahyaei1, Sepideh Arabzadeh2 and Parastoo Pourali1*

1Department of Medical Sciences, Shahrood Branch, Islamic Azad University, Shahrood, Iran. 2Biotechnology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.

Received on 08 August 2014 and accepted on 30 October 2014



Major purpose of this study was to explore an alternative and simple method for silver and gold nanoparticles bio-production by Escherichia coli. In the previous (routine) technique for nanoparticles bio-production, after culturing the bacteria, the bacterial culture supernatant was treated with aqueous solutions of silver nitrate and chloroauric acid ions. To perform bio-synthesis of silver and gold nanoparticles by the alternative method, unlike the routine one, the bacteria were subjected to the toxic metal ions at their MICs (minimal inhibitory concentration) immediate after inoculation to the medium. Bio-production of nanoparticles by these two methods was monitored through visible spectrophotometry, transmission electron microscopy (TEM) and X-ray diffraction analysis (XRD). The results showed that silver and gold nanoparticles were produced by both types of the routine and alternative techniques but the rate of bio-production was relatively more by the alternative one. Moreover, this type of bio-production is simpler, faster and cleaner than the previous one.

Keywords : Bio-production, Silver nanoparticles, Gold nanoparticles, Alternative method.