配位调控的量子点荧光编码对多组分有机磷农残可视化检测

Nowadays, organophosphorus (OP) pesticides are widely used in controlling insects in agriculture across the world but cause widespread contamination of air, water, soil and agricultural products, eventually leading to a serious threat to human and environment. Hence, the detection of OP pesticides easily and conveniently is highly in demand. Up to date, some analytical techniques including chromatography and enzyme-linked immunosorbent assay (ELISA) have been developed for the detection of OP pesticides. Unfortunately, these approaches are usually time-consuming, high cost and need complex sample pretreatment, which cannot meet the requirements for on-site, low cost and rapid detection of OP pesticides. On the basis of our previous work, we design a multi-emissive fluorescent composite probe for the highly sensitive and selective detection of OP pesticides by assembling different-color quantum dots (QDs) which have surface coordination-originated fluorescent responses to the target analytes. The OP pesticides and their degradation products can replace the ligand due to their higher affinity for the metal ions on the surface of QDs and cause a clear change in fluorescence colors and intensities of the coding probe. This analytical method of multiple signal output based on fluorescence coding technology realizes a sensitive, selective, fast and instant visual detection of OP pesticides in the environment and agricultural products and is expected to a new approach for OP pesticides detection.

有机磷农药是目前用量最大的杀虫剂，在环境和农产品中的残留对环境安全和人类健康已经构成严重威胁。常用的色谱和酶联免疫检测方法耗时长、成本高、样品前处理复杂、难以满足现场、快速、低成本检测的需求。本项目在前期工作的基础上，设计对不同颜色量子点表面具有适当配位能力并引发量子点荧光响应的有机配体，探索表面配体功能化的多色量子点的组装方法和原理，制备多颜色发射的复合量子点探针，实现对不同有机磷具有选择性响应的荧光编码。利用有机磷或者其降解产物对量子点表面的强配位能力，取代量子点表面的有机配体，从而引发编码探针多色荧光的颜色与强度比值改变，发展基于荧光编码技术的多重信号输出与解析方法，达到对多种有机磷的同步可视化检测。据此构建针对有机磷的高选择性、超灵敏、稳定可靠的快速可视化检测试纸或试剂盒，实现环境和农产品中有机磷农残的可视化检测。本项目的预期成果将为有机磷农残现场快速检测提供新手段。

本项目针对环境监测和食品安全领域有机磷农药残留快速廉价检测需求，利用量子点等纳米材料的光学特性，结合纳米化学和纳米颗粒表面的分子设计与修饰，发展并建立了荧光编码探针及其可视化检测分析方法。主要发现点和成果如下：（1）提出了几种新颖的纳米荧光编码探针设计原理和制备方法，实现了对痕量有机磷农药残留的快速敏感检测；（2）发展了基于比率荧光的可视化传感原理和分析方法，为快速、现场和廉价的生化分析提供了新手段；（3）成功构筑了纸质传感器和薄膜传感器，实现了痕迹量目标分析物（包括有机磷农药残留、爆炸物残留、重金属残留）的快速可视化检测，为发展复杂体系检测提供了理论和技术支持。上述研究工作取得了多项具有一定创新性和系统性的研究成果，部分研究工作已经在Anal. Chem.、Analyst、ACS Appl. Mater. Interfaces、Carbon、J. Mater. Chem. C等国际期刊上发表论文17篇。此外，还获得了国家授权发明专利3项。