Few-layered MoSe2 nanosheets as an efficient peroxidase nanozyme for highly sensitive colorimetric detection of H2O2 and xanthine

Abstract

Molybdenum-containing and selenium-containing enzymes are generally prevalent in the biosphere, and the active sites of these involve molybdenum and selenium respectively. Herein, we for the first time demonstrated that few-layered molybdenum selenide (MoSe₂) nanosheets possess intrinsic peroxidase-like activity. The few-layered MoSe₂ nanosheets were prepared by a simple liquid exfoliation method. The catalytic process of the MoSe₂ nanosheets accords with the Michaelis–Menten behavior and they have a higher affinity to both TMB and H₂O₂ compared to HRP. In addition, we established that the MoSe₂ nanosheets catalyze the oxidation of TMB by promoting the electron transfer process from TMB to H₂O₂. More importantly, we applied the MoSe₂ nanosheets to the field of biological detection by developing a highly sensitive and selective colorimetric detection of H₂O₂ and xanthine concentration. With these advantages, the few-layered MoSe₂ nanosheets have critical potential in the diagnostics and biomedical fields.