A turn-on fluorescence biosensor for sensitive detection of carbaryl using flavourzyme-stabilized gold nanoclusters
Jie Chen, Zhuqin Liu, Jinxin Fang, Yuanxiu Wang, Yi Cao, Wenjing Xu, Yingying Ma, Xiangyong Meng, Baojuan Wang
Abstract
Carbaryl contamination in food products has attracted much attention due to its threatening effects on human health. In this study, a novel flavourzyme-stabilized gold nanoclusters (Fla-AuNCs) biosensor with an average diameter of 1.37 nm was designed by a one-pot biomineralization method, which displayed blue fluorescence with an emission wavelength of 420 nm upon excitation at 360 nm. Meanwhile, it showed excellent photostability and maintained more than 90% of its original fluorescence intensity under an ultraviolet lamp for a period of 60 min or after storage in water solution at 4 °C for one month. Interestingly, the Fla-AuNCs acted as a fluorescent biosensor showing evident fluorescence enhancement after the addition of carbaryl via AIE and exhibited good linearity in the range of 25–200 nmol/L (R2 = 0.9958), with a detection limit of 2.34 nmol/L. Moreover, the sensing method was successfully utilized for the determination of carbaryl in fruit and vegetable samples with satisfactory recoveries of 95.4–103%. Hence, this study expands the range of protein templates for the synthesis of nanoclusters and develops a novel biosensor for agricultural product safety and monitoring.