基于卟啉金属有机框架的荧光探针检测有机磷农药残留

Detection of organophosphorus pesticide residues by the fluorescent probe based on porphyrin metal-organic framework

目的建立基于卟啉金属有机框架的荧光探针检测有机磷农药(organophosphorus pesticide,OPs)残留的方法。方法以金属有机框架(PCN-224-Mn)的类氧化酶活性、硫代胆碱和邻苯二胺之间的竞争作用,以及OPs对乙酰胆碱酯酶的抑制作用为基础,采用荧光法用于OPs残留的定量检测。结果以毒死蜱为模型,所构建的探针在0.05~50.00μg/mL的线性范围内对有机磷具有灵敏响应,检出限为29.6ng/mL。茶叶样品中毒死蜱残留的加标回收实验得到回收率为103.00%~112.00%,相对标准偏差小于3%。结论本研究不仅为精确、快速检测复杂样品中OPs残留提供了一种新的方法,而且为利用酶级联反应设计基于纳米酶的检测平台提供了新的见解。

Objective To establish a method for detecting organophosphorus pesticide(OPs)residues with fluorescent probes based on porphyrin metal-organic framework.Methods Based on the oxidase-like activity of the metal-organic framework(PCN-224-Mn),the competition between thiocholine and o-phenylenediamine,and the inhibition of OPs on acetylcholinesterase,the quantitative detection of OPs residues was performed by fluorescence method.Results Using chlorpyrifos as a mimic,the probe exhibited sensitive response to OPs in the linear range of 0.05-50.00μg/mL,and the limit of detection was 29.6 ng/mL.The recoveries of chlorpyrifos residue in tea samples were 103.00%‒112.00%,and the relative standard deviations were less than 3%.Conclusion This work not only provide a new method for the accurate and rapid detection of OPs residues in complex samples,but also offer new insights for the use of enzyme cascade reaction to design nanozyme-based detection platforms.