INTERACTION OF NANOMATERIALS WITH MICROBES AND THEIR CHARACTERIZATION

Abstract

Two different types of zinc oxide nanomaterials were synthesized, one capped with poly-ethylene glycol (PEG) and other was bare which was synthesized by solution free method. These nanoparticles were characterized by XRD, UV-Visible, SEM-EDAX, TEM and AFM. A commercially procured - Aldrich standard reference material of ZnO nanopowder of size less than 100 nm was used. The toxicity of the two types of synthesized ZnO nanomaterial and standard nanopowder, towards E. coli was studied by following the growth curve of E. coli with increasing concentrations (5 - 15 mg of nanomaterial per 100 ml of growth media) of nanomaterials where inhibition of growth was observed for higher concentrations. Inhibition in growth of E. coli was also complemented by Transmission Electron Microscopy and Atomic Force Microscopy, where the physical interaction of nanomaterial and E. coli was observed. The -cell deformation due to ZnO nanomaterial treatment could be observed from TEM and AFM images. In the presence of higher concentration of these nanomaterials cell rupture was observed under TEM. The PEG coated nanomaterial showed lesser anti-microbiological activity as compared to uncoated ZnO nanomateria