Effect of zno thin films on survival of Pseudomonas cells

Abstract

Thin films of ZnO nanoparticles obtained by magnetron sputtering deposition and wet chemical methods are investigated for their antibacterial effect on Gracilicutes- bacteria Pseudomonas putida. This bacterium is used as a sensitive standard in an international water quality test, ISO 10712:1995. It was chosen for toxic assessment of thin ZnO films, prepared by magnetron sputtering, sol-gel dip coating and chemical bath deposition methods. Washed and stained with Dead/Live bacterial kit suspension is evenly distributed on thin ZnO films and the survived cells are counted every 2 hours. Two microbiological methods are used: direct counting with epifluorescent microscope Leika DM 5500B and cultivation in nutrient medium. The results are processed with different statistical methods and show bactericidal effect of thin ZnO films. The surface relief of thin nanostructured film is crucial for the antibacterial effect and the fastest bactericidal effect demonstrates the ZnO film obtained by sol-gel dip coating. © 2012 Ivanova IA, et al.