AgPt/MoS2 hybrid as electrochemical sensor for detecting H2O2 release from living cells

Hydrogen peroxide (H2O2), as a biomarker in a series of physiological processes, plays a crucial role in investigating the pathogenesis of some diseases. The highly sensitive and selective detection of H2O2 release from living cells has aroused tremendous research interests. Herein, a non-enzymatic electrochemical H2O2 biosensor was constructed based on AgPt bimetallic nanoparticle-structured MoS2 nanohybrid (AgPt/MoS2) as an electrocatalyst. The AgPt/MoS2 nanohybrid was successfully synthesized by a facile wet-chemical method. Compared with AgPt nanoparticles, the AgPt/MoS2 nanohybrid exhibited significant enhancement in catalytic performance towards H2O2. The main factor is that MoS2 nanosheets as a supporting material promote AgPt nanoparticles to expose more active sites. The electrochemical response of the AgPt/MoS2 hybrid-based biosensor to H2O2 was linear in the range of 20 μM-4 mM, and the detection limit was calculated as 1.0 μM. To prove practicality, the biosensor was further applied to detect H2O2 release from living SMMC-7721 cells. These results indicate the potential applications of the developed biosensor in monitoring physiological processes.