Photocatalytic Removal of Pseudomonas Aeruginosa from Water Using Titanium Dioxide Nanoparticles and UV Irradiation

Background: Titanium dioxide (TiO2)-mediated photocatalysis has been found to be an efficient method of water treatment and is capable of degrading a wide range of organic pollutants and microbial agents with high efficiency. The microorganism Pseudomonas aeruginosa is resistant to chemicals and UV irradiation. Bacteria which are resistant to UV-induced oxidative damage of the cell membrane are susceptible to photocatalytic technology. The main objective of this research was to examine the photocatalytic removal of P. aeruginosa upon UV irradiation in the presence of TiO2 nanoparticles. Methods: Polluted water samples were prepared by the addition of P. aeruginosa colonies into water, followed by contact with UV, TiO2, or a combination of the two in separate stages. The effect of various parameters, including contact time, pH, and TiO2 concentration, on reaction efficiency was examined. Results: The highest efficiency of bacterial disinfection was achieved with UV irradiation in the presence of TiO2 nanoparticles, with complete (100%) removal of P. aeruginosa observed upon irradiation for 60 min in the presence of 0.4 g/L TiO2 under conditions of neutral pH. Conclusions: The results of this study suggest that from a technical and economic perspective, the UV/TiO2 process may be effectively applied for the disinfection of polluted water. This process could be considered a promising method of cleaning and purification, and applicable for water disinfection.