Green synthesis of silver nanoparticles using Rhodobacter Sphaeroides

The use of microorganisms in the synthesis of nanoparticles emerges as an eco-friendly and exciting approach. In this study, silver nanoparticles were successfully synthesized from AgNO3 by reduction of aqueous Ag+ ions with the cell filtrate of Rhodobacter sphaeroides. Nanoparticles were characterized by means of UV-vis absorption spectroscopy, X-Ray Diffraction (XRD), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). Crystalline nature of the nanoparticles in the fcc structure are confirmed by the peaks in the XRD pattern corresponding to (111), (200), (220) and (311) planes, bright circular spots in the selected are a electron diffraction (SAED) and clear lattice fringes in the high-resolution TEM image. Also, the size of silver nanoparticles was controlled by the specific activity of nitrate reductase in the cell filtrate.