Effect of the Photocatalyst under Visible Light Irradiation in SARS-CoV-2 Stability on an Abiotic Surface.

Uema, Masashi; Yonemitsu, Kenzo; Momose, Yoshika; Ishii, Yoshikazu; Tateda, Kazuhiro; Inoue, Takao; Asakura, Hiroshi

There is a worldwide attempt to develop prevention strategies against SARS-CoV-2 transmission. Here we examined the effectiveness of tungsten trioxide (WO3)-based visible light-responsive photocatalyst on the inactivation of SARS-CoV-2 under different temperatures and exposure durations. The viral titer on the photocatalyst-coated glass slides decreased from 5.93 ± 0.38 logTCID50 /mL to 3.05 ±. 25 logTCID50/mL after exposure to 3,000 lux of the visible light irradiation for 6h at 20℃. On the other hand, lighting without the photocatalyst, or the photocatalyst-coat without lighting retained viral stability. Immunoblotting and electron microscopic analyses showed the reduced amounts of spike protein on the viral surface after the photocatalyst treatment. Our data suggest a possible implication of the photocatalyst on the decontamination of SARS-CoV-2 in indoor environments, thereby preventing indirect viral spread.