Zixuan Zhao, Yaxin Guo, Jie Wei
Mar 1, 2021
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Influential Citations
13
Citations
Journal
Journal of Analysis and Testing
Abstract
Abstract Hypoxanthine (Hx) is an important freshness indicator reflecting the initial freshness of aquatic products. In this work, a novel fluorescence method was established based on cysteine functionalized copper nanoclusters (Cys-CuNCs) for monitoring Hx in fish. The as-synthesized Cys-CuNCs exhibit favorable fluorescent property. Importantly, the fluorescence can be quenched significantly when the solution contained a small amount of hydrogen peroxide (H 2 O 2 ), which was due to both the oxidation of H 2 O 2 towards Cys-CuNCs and the resulting Cu(II). Owing to that Hx can generate H 2 O 2 under dissolved oxygen and xanthine oxidase (XOD), a fluorescent method for Hx was established. Under the optimal conditions, the Hx concentration in the range of 8–400 μmol/L has a good linear relationship with the fluorescence quenching efficiency, and the detection limit is 0.7 μmol/L. Finally, the as-established sensor was applied to determine Hx content in carp. By comparing to the total volatile basic nitrogen (TVB-N) results, the proposed method was feasible in the evaluation of carp freshness. Graphic abstract