Photocatalytic Inactivation of Co-Culture of E. coli and S. epidermidis Using APTES-Modified TiO 2 .

The presented work shows the antibacterial activity of TiO 2 photocatalysts modified by 3-aminopropyltriethoxysilane (APTES). The APTES-functionalized TiO 2 samples were obtained by the solvothermal process followed by calcination. The antibacterial activity of APTES/TiO 2 samples was evaluated with two species of bacteria, Escherichia coli and Staphylococcus epidermidis , under artificial solar light (ASL) irradiation. The used bacteria are model organisms characterized by negative zeta potential (approx. -44.2 mV for E. coli and -42.3 mV for S. epidermidis ). For the first time, the antibacterial properties of APTES-functionalized TiO 2 were evaluated against mono- and co-cultured bacteria. The high antibacterial properties characterized the obtained APTES-modified nanomaterials. The best antibacterial properties were presented in the TiO 2 -4 h-120 °C-300 mM-Ar-300 °C sample (modified with 300 mM of APTES and calcined at 300 °C). The improvement of the antibacterial properties was attributed to a positive value of zeta potential, high surface area, and porous volume.