基于表面分子印迹聚吡咯纳米纤维同时选择性高效提取食品中多种非法添加物的效能及应用研究

Illicit additives in food pose long-term hazards to food safety and regulatory credibility. An efficient, fast and simple sample pretreatment is a precondition for detection of illicit additives in food. Molecularly imprinted polymers can specifically extract target molecules and have been widely used in complex sample pretreatment. But its problems of template leakage and single recognition sites lead to low sensitivity and low throughput, which impacts on the efficiency of analysis. The project intends to combine versatility of polypyrrole and advantages of nanofibers to prepare a multi-template surface molecularly imprinted polypyrrole nanofibers sorbent which exhibits specific selectivity, high binding capacity, fast mass transfer and high-throughout features. A simple sample preparation method based on the novel sorbent is developed for simultaneously selectively efficient extraction and enrichment of multi-illicit additives from food. Firstly, we propose the thoughts for preparing surface molecularly imprinted polypyrrole nanofibers. And its imprint-recognition mechanism and outstanding efficiency are systematically investigated. Subsequently, multi-template surface molecularly imprinted polypyrrole nanofibers are prepared and then applied to illicit additives analysis. This project will broaden the research theory and preparation method of surface molecularly imprinted nanofibers and molecularly imprinted polypyrrole, and also will provide a fast and accurate methodology for analysis of multi-illicit additives in food.

食品中非法添加物长期危害食品安全和监管公信。高效、快速、简便的样品前处理是快速准确检测食品中非法添加物的前提。分子印迹材料可以特异性地提取目标物，被广泛应用于食品等复杂样品前处理，但存在模板泄露和单模板识别问题，导致检测灵敏度低、不能同时选择性提取多种目标物，极大地影响了分析效率。本项目旨在将多功能性聚吡咯与纳米纤维相结合，制备高选择性、高吸附容量、高通量、低传质阻力的表面分子印迹聚吡咯纳米纤维，构建可实现食品中多种非法添加物同时选择性高效提取和富集的样品前处理方法，提高分析效率。首先提出表面分子印迹聚吡咯纳米纤维的制备方法，探明其印迹-识别机理和高效能，在此基础上，研制多模板表面分子印迹聚吡咯纳米纤维，研究其在食品非法添加物检测中的应用。本项目的开展，将拓展表面分子印迹纳米纤维和分子印迹聚吡咯的相关研究理论和制备方法，为食品中多种非法添加物的分析检测提供快速准确的方法学基础。

表面分子印迹聚合物以其模板易脱除、传质速率快、有效印迹位点多等优点，在高效、高选择性分离分析中展现出巨大的应用前景。提高样品前处理方法的选择性是实现复杂体系中目标物分离分析的关键科学问题之一，基于表面分子印迹聚合物的固相萃取技术为其提供了有效解决途径。本项目围绕表面分子印迹聚吡咯纳米纤维的制备及应用，开展了以下研究工作，首先建立了表面分子印迹聚吡咯纳米纤维膜（PPy MIM）的制备技术，首次从理论角度论证了聚吡咯分子印迹聚合物的形成机制，然后将所得黄曲霉毒素PPy MIM用作固相萃取吸附剂，通过与高效液相色谱质谱联用，建立了一种灵敏、快速检测食品中黄曲霉毒素的新方法；发展了多模板表面分子印迹聚吡咯纳米纤维膜（Multi-PPy MIM），成功应用于环境水中痕量双酚A、壬基酚和雌二醇的高效、高选择性分离检测。此外，为提高聚吡咯纳米纤维膜（PPy NFsM）的吸附性能，从材料的分子结构和形态结构两个方面着手改进，开发了3D超亲水PPy NFsM，解决了传统PPy NFsM传质阻力的问题；制备了双重修饰的吡咯/苯胺共聚复合纳米纤维膜，弥补单一聚合物的固有缺陷，实现了多种全氟及多氟化合物的同时高效去除。本项目从理论和实验角度证明了制备PPy MIM的可行性与可靠性，并为基于PPy MIM固相萃取的样品预处理新技术应用于实际样品分析提供了理论和实践基础。