Designing CoS1.035 Nanoparticles Anchored on N-Doped Carbon Dodecahedron as Dual-Enzyme Mimics for the Colorimetric Detection of H2O2 and Glutathione

In recent years, the exploration of the nanozyme, an artificial enzyme with the structure and function of natural enzymes, has become a hot topic in this field. Although significant progress has been made, it is still a huge challenge to design nanozymes with multiple enzyme-like catalytic activities. In this work, we have successfully fabricated a colorimetric sensing platform to mimic peroxidaselike and oxidase-like activities by the CoS1.035 nanoparticles decorated N-doped carbon framework porous dodecahedrons (abbreviated to CoS1.035/N-C PDHs). And the catalytic mechanism of CoS1.035/N-C PDHs toward the peroxidase-like and oxidase-like activities is systematically explored. The results display that CoS1.035/N-C PDHs can catalyze the oxidation of the colorless substrate 3,3,'5,5'-tetramethylbenzidine (TMB) into blue oxidized TMB (ox-TMB) by disintegrating H2O2 or the physically/chemically absorbed O-2 into different ROS species (center dot OH or O-2(center dot-)) in the presence or absence of H2O2. Therefore, on the basis of the dual-enzyme mimic activities of CoS1.(035)/N-C PDHs, the bifunctional colorimetric sensing platform is established for H2O2 detection with a wide linear range of 0.5-120 mu M and glutathione detection with a linear range of 1-60 mu M, respectively. This work provides an efficient platform for dual-enzyme mimics, expanding the application prospect of Co-based chalcogenides as enzyme mimics in biosensing, medical diagnosis, and environment monitoring.