Synthesis of PVP-functionalized ultra-small MoS₂ nanoparticles with intrinsic peroxidase-like activity for H₂O₂ and glucose detection

Polyvinylpyrrolidone (PVP)-modified MoS₂ nanoparticles (PVP-MoS₂ NPs) with d = 5 nm and in high purity and yield were prepared by a facile one-pot hydrothermal method. Cytotoxicity and hemolysis studies demonstrated that PVP-MoS₂ NPs show good biocompatibility. The PVP-MoS₂ NPs exhibited remarkable peroxidase-like catalytic activity, which was similar to that of horseradish peroxidase (HRP). Based on this peroxidase-like activity, a platform for colorimetric detection of H₂O₂ was established. We have found that these NPs have high sensitivity to detect H₂O₂ with a nearly linear range between 2.0 × 10^-6 mol L^-1 and 1.5 × 10^-4 mol L^-1. Furthermore, the PVP-MoS₂ NPs were also used for glucose measurement in serum by quantifying the released H₂O₂ in the presence of glucose oxidase. The linear range for glucose detection was from 1.0 × 10^-3 mol L^-1 to 1.0 × 10^-2 mol L^-1. This work will pave a way for the high-throughput synthesis of other ultra-small transition metal dichalcogenide (TMDs) NPs. Such enzyme-mimic nanomaterials could be a useful tool for medical diagnosis.