Synthesis of TiO2 nanoparticles using microorganisms

A low-cost green and reproducible microbes (Lactobacillus sp. and Sachharomyces cerevisae) mediated biosynthesis of TiO2 nanoparticles is reported. The synthesis is performed akin to room temperature in the laboratory ambience. X-ray and transmission electron microscopy analyses are performed to ascertain the formation of TiO2 nanoparticles. Individual nanoparticles as well as a few aggregate having the size of 8-35 nm are found. Concentric Scherrer rings in the selected area electron diffraction pattern indicated that the nanoparticles are having all possible orientations. A possible involved mechanism for the biosynthesis of nano-TiO2 has also been proposed in which pH as well as partial pressure of gaseous hydrogen (rH(2)) or redox potential of the culture solution seems to play an important role in the process. (C) 2009 Elsevier B.V. All rights reserved.