Bio-organic-inorganic hybrid photocatalyst, TiO2 and glucose oxidase composite for enhancing antibacterial performance in aqueous environments

Abstract

TiO2-UV photocatalytic systems have been widely studied and applied for removing pathogenic bacteria in water treatment. We created a hybrid catalyst (TiO2-GOx) by combining the inorganic photocatalyst (TiO2) and the organic biocatalyst, glucose oxidase (GOx) that can be activated using UV radiation and glucose to generate a reactive oxygen species (ROS). More rapid disinfection of bacteria in the presence of UV and glucose was observed using the hybrid catalyst (TiO2-GOx) than using TiO2 particles. GOx generates H2O2 and superoxide under glucose-rich conditions in which heterotrophic bacteria grow quickly, this H2O2 and superoxide can act as disinfection agents along with the ROS (such as OH radicals) generated from the photocatalytic activation resulting from the interaction between UV radiation and TiO2. Therefore, the rapid disinfection activity of TiO2-GOx can be attributed to the enhancement of ROS generation due to the high catalytic activity of TiO2-GOx in the combined glucose-UV rich environment. The hybrid catalyst (TiO2-GOx) can be useful for disinfecting field water or wastewater with a high concentration of carbon sources such as glucose that can be assimilated by heterotrophic bacteria.