▎ 摘　　要

A simple protocol for in situ growth of Cu2-xSe nanoparticles on graphene oxide hybrids (Cu2-xSe/rGO) acting as an efficient nanozyme is developed and thus a sensitive visual detection method of cancer cells is proposed. The Cu2-xSe/rGO heterogeneous nanomaterials have been proven to exhibit high peroxidase- like activity to catalyze the reaction of the peroxidase substrate in the presence of hydrogen peroxide. Herein, we used Cu2-xSe/rGO as a signal transducer to develop a colorimetric assay for the direct detection of cancer cells and a total of 63 cancer cells (MCF-7) can be distinguished by naked-eye observation. The results showed that the Cu2-xSe/rGO hybrids could be the promising nanozyme mimetics for potential applications in bioanalytical fields.