Biosynthesis of Gold Nanoparticle using Cell-free Extract of Clinical Isolates Staphylococcus Aureus and Escherichia Coli
Malaysian Journal of Medical and Biological Research
Present study reports on biological synthesis of gold nanoparticles using cell free extract of Staphylococcus aureus and Escherichia coli. The cold extract is allowed to react with both 1mM and 10 mM solutions of HAuCl4 which showed a colour change from yellow to dark cherry red after 1 hr. Gold nanoparticle formation is confirmed with UV-Visible spectrophotometer at 547nm.The 10mM concentration is found to be better for synthesis of more NPs using E. coli. XRD pattern exhibited 2θ
... ted 2θ values38.18o, 44.39o, 64.58o, 77.55o of 2θ value, corresponding to Bragg's diffraction at 111, 200, 220 and 311 plane of lattice structure closely matching with the standard values given in ICDD reference file. SEM analysis revealed morphological characteristics of nanoparticles of different sizes ranging from 70 to 200 nm. Thus, the present study throws new light on the suitability of E. coli as an alternative for conventional methods of chemical synthesis of gold nanoparticles.