Microbial synthesis of semiconductor lead sulfide nanoparticles using immobilized Rhodobacter sphaeroides

A reliable and eco-friendly process for the synthesis of nanoparticles such as using biological systems has been developed. In this study, we synthesized PbS nanoparticles with the average particle size ca. 10.5 +/- 0.15 nm using immobilized Rhodobacter sphaeroides. The PbS nanoparticles were characterized by X-ray diffraction (XRD). transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive analyses of X-rays (EDX) and Uv-vis optical absorption. Culture time, as an important physiological parameter for R. sphaeroides growth, could significantly control the size of the biosynthesized lead sulfide nanoparticles. Extracellular synthesis of nanoparticles by immobilized mass could be highly advantageous from the point of view of synthesis in large quantities and easy downstream processing. (c) 2009 Elsevier B.V. All rights reserved.