▎ 摘　　要

In this study, pyrene was used as a fluorescent dye for peptides. A sensitive, selective, and simple sensor platform was built to detect chymotrypsin based on the covalent binding of peptides to gold nanoparticles (AuNPs) and GO. NaBr as a robust back-filler on gold ensured that the peptides were attached on the surface of AuNPs. Chymotrypsin was added to cleave a specific site on the peptide. Fluorescence was restored after the release of the fluorescent group. The limit of detection was 7.394 pg mL(-1). Our method could be applied to real samples.