Potential and Risk of the Visible Light Assisted Photocatalytical Treatment of PRD1 and T4 Bacteriophage Mixtures

Abstract

In current study UV light and visible light activated photocatalytic inactivation treatment was applied to the less commonly studied subjects, namely bacteriophages PRD1, T4 and their mixture. By using UV light irradiation and high efficiency P25 TiO2 photocatalyst powders it was demonstrated that individually and in mixture PRD1 bacteriophage is particularly vulnerable to the photocatalytic inactivation and in just approximately 20 min its infectivity is reduced by 100 %. As for the T4 bacteriophage, it has been reported that under UV irradiation T4 triggers self-repair and replication mechanisms therefore under same photocatalytic inactivation conditions infectivity reduction reaches just 60 %. Surprisingly, by studying visible light photocatalytic treatment efficiency of PRD1 and T4 bacteriophage mixture we identified that T4 bacteriophage potentially triggers the same self-repair and replication mechanism as it does under UV light. Moreover, by using two different types of visible light activated photocatalysts we determined that when efficiency of the used photocatalyst is too small the overall infectivity of the T4 bacteriophage can significantly surpass the corresponding property of the untreated control group.

Influence of the Metabolic Activity of Microorganisms on Disinfection Efficiency of the Visible Light and P25 TiO2 Photocatalyst

“…Our earlier study with visible light activated carbon-doped TiO2 photocatalyst showed effective inactivation of PRD1 and T4 bacteriophages [38]. C-doped TiO2 traditionally has a narrower band gap and additional electron energy levels [23,24].…”

Synergistic Generation of Reactive Oxygen Species by Visible Light Activated TiO2 and S. Enterica Interaction

“…____________________________________________________________________________ 2021 / 25 980 Titanium dioxide is arguably the most promising photocatalytic material. It is non-toxic and is widely used in various fields including water cleaning from organic pollutants, microorganisms and viruses [6]- [8]. Unfortunately, the band gap value of the pristine TiO2 is larger than the energy of the visible light photons.…”