Alcohol oxidase-driven in situ synthesis of BSA-stabilized copper nanoclusters for precise monitoring of methyl mercaptan in food samples

Abstract Owing to lack of the effective chromogenic groups, a convenient, precise, and real-time assay for the detection of methyl mercaptan (CH3SH) still remains many huge challenges, but it is of great importance to the food and agribusiness related industries. In this work, we proposed an interesting and efficient fluorescence sensing strategy-based alcohol oxidase (AOX)-triggered in situ synthesis of bovine serum albumin-stabilized copper nanoclusters (BSA-CuNCs) for sensitive and selective detection of CH3SH. In the presence of CH3SH, AOX-assisted O2 could catalyze it to be H2O2, which could further trigger BSA-Cu2+ system to in situ synthesize of BSA-CuNCs, emitting fluorescence signals. On this basis, CH3SH concentration-dependent fluorescence emission of BSA-CuNCs was observed, thus allowing for developing a novel fluorescence sensing platform for reporting the levels of CH3SH with a broad linear range from 1.0 to 300.0 μM and a low detection limit of 0.19 μM. More significantly, we exploited this sensing strategy to monitor CH3SH in real ham samples with acceptable results. This work gives a new insight into applying in situ synthesis strategy to develop a new category of fluorescence sensing platform, achieving convenient, low-cost, reliable, and precise measurements in real food and agriculture-related systems, thereby manifesting a promising potential in food safety monitoring.