Biocidal effects of photocatalytic semiconductor TiO2

Photocatalytic action of the commercial TiO2 was the subject of study on the destruction of the microbes within the biofilms. The TiO2 powder was characterized by X-ray diffraction (XRD) for identifying its type and the particle size was determined. The biofilm was allowed to form over TiO2 coatings over glass slides irradiated with polychromatic light for different time durations and distances. It indicates that a five-fold decrease in bacterial count due to the formation of H2O2 at TiO2/biofilm interface. The formation of H2O2 at the TiO2/biofilm interface is estimated and it does not destroy the entire bacterial population within the biofilm. Bacterial killing effect is supported by FT-IR analysis.