▎ 摘　　要

Herein, a dual-emission ratio fluorescence probe for copper ions (Cu2+)-based bleomycin (BLM) detection was established for the first time. The ratio fluorescence probe, nitrogen doped graphene quantum dots@gold nanoclusters (NGQDs@AuNCs), showed two well-resolved emission peaks at 440 nm and 580 nm respectively. Fluorescence intensity of AuNCs at 580 nm can be quenched by Cu2+ but restored in the presence of BLM, while fluorescence intensity of NGQDs at 440 nm remained unchanged throughout the process. The Cu2+-triggered fluorescence quenching can be attributed to aggregation-induced quenching mechanism, and the strong affinity between Cu2+ and BLM can make the quenched fluorescence turn on. Under optimal conditions, the BLM can be detected in the range of 0.8-1800 nM and the limit of detection (LOD) was 0.27 nM. Furthermore, the established method in the application of human serum samples has been confirmed.