Inactivation of MS2 bacteriophage by titanium dioxide nanoparticles in the presence of quartz sand with and without ambient light

Abstract

Virus inactivation by nanoparticles (NPs) is hypothesized to affect virus fate and transport in the subsurface. This study examines the interactions of viruses with titanium dioxide (TiO₂) anatase NPs, which is a good disinfectant with unique physiochemical properties. The bacteriophage MS2 was used as a model virus. A series of batch experiments of MS2 inactivation by TiO₂ NPs were conducted at room temperature (25°C), in the presence and absence of quartz sand, with and without ambient light. Three sets of experiments were performed in phosphate buffered saline solution (PBS) and one in distilled deionized water (ddH₂O). The virus inactivation experimental data were satisfactorily fitted with a pseudo-first order expression with a time dependent rate coefficient. Quartz sand was shown to affect MS2 inactivation by TiO₂ NPs both in the presence and absence of ambient light, because, under the experimental conditions of this study, the quartz sand offers a protection to the attached MS2 against inactivation. Moreover, it was shown that low TiO₂ concentration (10mg/L) affected only slightly MS2 inactivation with and without ambient light. Furthermore, PBS hindered MS2 inactivation by TiO₂ NPs.

Keywords: Ambient light; Darkness; Inactivation; MS2; Quartz sand; TiO(2).