Photocatalytic inactivation of phage Qβ by immobilized titanium dioxide mediated photocatalyst

Photocatalytic inactivation of virus by immobilized TiO₂ was investigated using RNA phage Qβ as a model. TiO₂-coated tiles, developed for interior sterilisation, were used as immobilized photocatalyst. 2.2 log Qβ was inactivated by immobilized TiO₂ mediated photocatalysis by 1h irradiation with near UV black light at an intensity of 3.6×10⁻³W/cm². Experiments with a slurry TiO₂ reactor were also performed as a reference for the inactivation kinetics study. Photocatalytic Qβ inactivation was expressed by first-order kinetics as the initial concentration of the phage Qβ varied. The inactivation rate constant was proportional to the light intensity in the range of 3–8×10⁻³W/cm² of black light with immobilized TiO₂ photocatalyst. Broth introduced with phage into the reaction solution inhibited inactivation. No noticeable difference in inactivation was observed between germicidal lamp irradiation with and without immobilized TiO₂.