TiO supported single Ag atoms nanozyme for elimination of SARS-CoV2.

The outbreak of SARS-coronavirus 2 (SARS-CoV2) has become a global health emergency. Although enormous efforts have been made, there is still no effective treatment against the new virus. Herein, a TiO supported single-atom nanozyme containing atomically dispersed Ag atoms (Ag-TiO SAN) is designed to serve as a highly efficient antiviral nanomaterial. Compared with traditional nano-TiO and Ag, Ag-TiO SAN exhibits higher adsorption (99.65%) of SARS-CoV2 pseudovirus. This adsorption ability is due to the interaction between SAN and receptor binding domain (RBD) of spike 1 protein of SARS-CoV2. Theoretical calculation and experimental evidences indicate that the Ag atoms of SAN strongly bind to cysteine and asparagine, which are the most abundant amino acids on the surface of spike 1 RBD. After binding to the virus, the SAN/virus complex is typically phagocytosed by macrophages and colocalized with lysosomes. Interestingly, Ag-TiO SAN possesses high peroxidase-like activity responsible for reactive oxygen species production under acid conditions. The highly acidic microenvironment of lysosomes could favor oxygen reduction reaction process to eliminate the virus. With hACE2 transgenic mice, Ag-TiO SAN showed efficient anti-SARS-CoV2 pseudovirus activity. In conclusion, Ag-TiO SAN is a promising nanomaterial to achieve effective antiviral effects for SARS-CoV2.