黄瓜中多菌灵、啶虫脒和毒死蜱的荧光检测

Fluorescence detection of carbendazim, acetamiprid and chlorpyrifos in cucumber

中文关键词:  功能石墨烯量子点  光学探针  荧光共振能量转移  荧光检测  生鲜食品

英文关键词:functional graphene quantum dots  optical probe  fluorescence resonance energy transfer  fluorescence detection  fresh food

中文摘要:

      目的 建立一种基于功能化石墨烯量子点与氧化石墨烯之间的荧光共振能量转移原理测定黄瓜中多菌灵、啶虫脒和毒死蜱的荧光分析方法。方法 通过一步法制备半胱氨酸和组氨酸功能化石墨烯量子点。氨基修饰的农药适配体共价连接到石墨烯量子点的石墨烯片边缘, 然后引入氧化石墨烯猝灭其荧光。在农药存在下, 适配体与农药分子发生特异性结合形成稳定的杂合物而不能被氧化石墨烯所吸附, 造成石墨烯量子点从氧化石墨烯表面脱落且荧光恢复。结果 所制备的石墨烯量子点由2~3层石墨烯片组成, 平均片径大小约为3.6 nm, 360 nm紫外光激发可产生强的蓝色荧光。当多菌灵、啶虫脒和毒死蜱的浓度分别在1.0~500.0、0.1~100.0和2.5~500.0 nmol/L的范围内, 荧光强度随农药浓度的增加而线性增长。检出限依次是0.47、0.04和0.80 nmol/L。结论 通过石墨烯量子与氧化石墨烯之间高效的荧光共振能量转移, 本研究建立了黄瓜中多菌灵、啶虫脒和毒死蜱的荧光检测方法。本方法在选择性、灵敏度和重现性等方面具有明显优势, 可广泛用于食品和环境样品中农兽药残留的快速分析。

英文摘要:

      Objective To establish a fluorescence analysis method for the determination of carbendazim, acetamiprid and chlorpyrifos in cucumber based on the principle of fluorescence resonance energy transfer between functional graphene quantum dots and graphene oxide. Methods Cysteine and histidine functional graphene quantum dots were prepared by one-step method. Amino modified pesticide aptamers were covalently attached to the graphene sheet edge of graphene quantum dots, and then graphene oxide was introduced to quench its fluorescence. In the presence of pesticide residues, aptamers specifically bound with pesticide molecules to form stable heterozygotes, which could not be adsorbed by graphene oxide, resulting in graphene quantum dots falling off from the surface of graphene oxide and fluorescence recovery. Results The prepared graphene quantum dots were composed of 2?3 graphene sheets with an average diameter of about 3.6 nm, strong blue fluorescence could be generated by 360 nm ultraviolet excitation. When the concentrations of carbendazim, acetamiprid and chlorpyrifos were in the range of 1.0?500.0, 0.1?100.0 and 2.5?500.0 nmol/L respectively, the fluorescence intensity increased linearly with the increase of pesticide concentration. The detection limits were 0.47, 0.04 and 0.8 nmol/L. Conclusion A fluorescence detection method for carbendazim, acetamiprid and chlorpyrifos in cucumber is established by efficient fluorescence resonance energy transfer between graphene quantum and graphene oxide. This method has obvious advantages in selectivity, sensitivity and reproducibility, it can be widely used for the rapid analysis of agricultural and veterinary drug residues in food and environmental samples.