SARS-CoV-2 viability after exposure to titanium dioxide coated tiles

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission occurs via airborne droplets and surface contamination. Droplets or other body fluids from infected individuals can contaminate surfaces and viable virus has been detected on such surfaces, including surgical masks, for hours, even days depending on different factors including humidity, temperature and type of surface. Titanium dioxide (TiO2) coating of surfaces is a promising infection control measure, though to date has not been tested against SARS-CoV-2.

Methods

Virus stability was evaluated on the following surfaces: sterile untreated Sterilin standard Petri dish; TiO2- and TiO2–Ag (Ti:Ag atomic ratio 1:0.04)-coated 45 x 45 mm ceramic tiles. After coating the tiles were stored for 2–4 months before use. Surfaces were exposed (610 lx, ambient laboratory light) for 1 h before the start of each experiment to ensure a steady state of radical generation. We tested the stability of both SARS-CoV-...