Effect of TiO2 nanoparticles on the structure and activity of catalase

TiO 2 nanoparticles are the most widely used metal oxide nanoparticles and have oxidative toxicity. Catalase is an important antioxidant enzyme . Here the understanding of an effect of TiO 2 nanoparticles on the activity and structure of catalase is crucial to characterize the toxicity of TiO 2 nanoparticles. These experimental data revealed that TiO 2 nanoparticles could bind to catalase by the electrostatic and hydrogen bonding forces. On binding TiO 2 nanoparticles, catalase got destabilized with the decrease of α-helices content, the solvent polarity of environment around the fluorescence chromophores on catalase were also affected. In addition, TiO 2 nanoparticles also affected the activity of catalase. TiO 2 nanoparticles acted as an activator of catalase activity at a low molar concentration and as an inhibitor at a higher molar concentration. With regard to human health, the present study could provide a better understanding of the potential nanotoxicity of TiO 2 nanoparticles.