宽色度演变的可视化半定量荧光纳米试纸对多组分农残的快速检测

Rapid and on-site analytical strategies are highly needed owing to the more pollution from pesticides in environments, and paper sensors have some advantages including visualization, low-cost, rapid and on-site. However, optical absorption-based analytical paper can be used to detect by change of light intensity, and it is only for quanlitative analysis owning to bad anti-interference and low sensitivity. Furthermore, common fluorescent paper sensors cannot be extended for wider applications because of narrow spectral range, low color resolution, and poor quantitative ability. This project aims at the design of multiple nano test papers by adjusting the ratio of composition of multicolor nano probes to achieve wide fluorescent chromaticity evolution, and finally realization of high-throughout, semi-quantitative and visual detection of dosage-sensitive and multiple organophosphorus pesticide residues. (1) Explore the methods for the surface functionalization and selection of specific ligands of multi colored fluorescent nanoparticles to prepare the wide spectrum emission nanoprobes; (2) Develop the principles for multicolor composition of fluorescent nanoprobes and adjusting ratio of wide fluorescent chromaticity to get the visual and quantitative nanoprobes with high-resolution fluorescent chromaticity; (3) Elucidate the signal response between organophosphorus pesticides and probes and their inherent modes for dosage-sensitive fluorescent chromaticity evolution, and establish the signal reading and analysis principle based on the dose-sensitive wide spectrum fluorescence evolution technique; (4) Utilize multiple test papers with dose-sensitive wide spectrum fluorescence evolution combined with microfluidics technique, realize high-throughout, semi-quantitative and visual detection of dosage-sensitive and multiple organophosphorus pesticide residues. The expected results of this project will provide a new way of thinking and technical means for the development of quantitative fluorescent test paper analysis method.

农药污染严重危害生态环境和人类健康，发展快速现场分析技术至关重要。分析试纸具有低成本、可视化及快速现场等优点，光吸收分析试纸利用光强度变化来检测，其抗干扰性差、灵敏度不高，只能定性分析。现有荧光试纸则存在光谱变化范围窄、色度分辨低、定量能力差等不足。本项目拟通过调控多色纳米探针组合比率获得荧光宽色度演变，结合微流控技术发展多通道纳米试纸，实现对多组分有机磷农药残留的快速检测。（1）探索多色纳米粒子表面功能化修饰及特异性配体筛选优化，合成宽光谱发射荧光探针；（2）建立荧光探针多颜色组合和宽色度比率调配原理，设计高分辨色度调控的可视化分析探针；（3）阐明剂量敏感农药分子和荧光探针色度演变间的内在规律，建立基于高分辨荧光色度演变的信号读取与分析方法；（4）结合微流控技术构建多通道试纸，实现对多组分有机磷农药残留的可视化半定量分析。预期将为发展高通量可视化半定量试纸分析方法提供科学依据和技术支撑。

在国家自然科学基金委的大力支持下，按照项目任务书的要求开展了相关研究工作，完成了计划书中所有研究任务，达到了预期的研究目标。通过调控多色纳米探针组合比率获得荧光宽色度演变，结合微流控技术发展多通道纳米试纸，实现了对多组分有机磷农药残留的快速检测。有机磷农药在农牧产品中的广泛残留，对食品安全和人类健康构成严重的威胁，已经引起中国政府和国际社会的高度关注。传统的农药残留检测主要依赖大型、昂贵和耗时的实验室分析仪器，无法满足农药残留的现场、快速和低成本的要求，因此，发展超灵敏快速准确的检测农药残留的先进传感材料和检测技术具有重要的科学意义、巨大的经济价值和重要的社会意义。针对传统功能材料的结合容量低和结合动力学慢的困难，我们综合运用材料科学、仿生学和纳米技术的手段，成功制备出性能优越的功能纳米结构。我们发展了基于剂量敏感荧光宽色度演变的纳米试纸实现对环境及农产品中的多组分有机磷农药残留的同步现场快速及半定量可视化分析。通过对探针颜色组合和比率调配的探索以及特异性有机配体和有机磷农药分子之间敏感作用的研究，进而设计和制备剂量敏感的宽光谱发射荧光纳米组合探针，并结合微流控技术构建基于剂量敏感荧光色度演变的多通道纳米试纸，实现对环境和农产品中的多组分有机磷农药残留的低成本、快速、可视化半定量快速分析。为发展荧光快速分析的检测传感器提供了理论和技术支持。上述研究工作取得了多项具有创新性和系统性的研究成果，部分研究工作已经在高影响力的国际期刊Analytical Chemistry (4篇) 、Journal of Hazardous Materials(4篇)、Chemical Engineering Journal (2篇)、Sensors and Actuators B: Chemical （2篇）等上发表论文18篇。本项目的完成为发展新一代敏感材料和检测器件及基于荧光光谱的快速检测提供新手段,为发展化学生物环境传感器提供理论基础与技术支撑。