Understanding the role of oxo and peroxido species in the glutathione peroxidase (GPx)-like activity of metal based nanozymes

Nanomaterials having enzyme-like activities (nanozymes) attract significant attention. Particularly, metal-based nanozymes that exhibit superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities find applications in controlling the redox state of the cells. It has been shown that V2O5 functionally mimic the GPx enzyme by catalytically reducing H2O2 in the presence of glutathione (GSH). In this paper, we discuss the role of oxo and peroxido species in the GPx activity of V2O5 and MoO3. A detailed mechanistic study reveals that the GPx activity of these materials depends on the reactivity of oxo moiety on the surface of the material with H2O2 to form the peroxido linkages.