磁温双响应型碳点印迹荧光传感体系构建及对双酚A可控分子识别传感机理研究

The escalating food safety problems in recent years make it more urgent to develop an accurate, rapid and high selective food detection technology. Fluorescence assay, due to its high sensitivity, simple operate, good selectivity and short response time, has attracted much attention. Carbon dot with its excellent luminescent properties and good biocompatibility, have become an ideal material for designing fluorescent probe. Bisphenol A, is commonly used in food and drink packaging, as an environmental hormone, causing risks for environment as well as for human health. In this project, bisphenol A as the object of study, fluorescent carbon dots as signal conduction material, N-isopropylacrylamide as thermo sensitive functional monomer, magnetic metal organic framework as a matrix, magnetic and thermo-dual responsive fluorescent sensing material based on carbon dots embedded molecular imprinted polymer will be designed and constructed by a surface imprinting technique. By employing computer molecular simulation, we aim to expound its temperature-control imprinting and recognition process, and reveal the fluorescence response mechanism from the angle of molecular level. Based on this fluorescent smart material, a novel sensing system with the function of temperature response, molecular recognition, fluorescent sensing and magnetic separation will be developed, and is expected to realize rapid, high sensitive and selective detection for bisphenol A in food. The strategy proposed here will provide a theoretical basis and methods for reference for development of multi-functional intelligent fluorescent material and construction of fluorescent sensing system, meanwhile it is of great significance for promoting the development of food detection technology to ensure food safety.

近年来食品安全问题不断升级，发展精准、快速、高选择性食品检测技术迫在眉睫。荧光检测法具有灵敏度高、方法简便、选择性好、响应时间短等优点而备受青睐。碳点，以其优异的荧光特性、良好的生物相容性，成为设计发光探针的理想材料。本研究以食品包装中广泛存在的环境激素类物质-双酚A为研究对象，荧光碳点作为信号传导物质，N-异丙基丙烯酰胺作为温敏性单体，磁性金属有机框架作为基质，采用表面分子印迹技术，设计构筑具有磁、温双重响应的碳点-分子印迹智能荧光传感材料。采用计算机分子模拟技术，从分子角度阐明温度调控下的印迹和识别过程，揭示荧光响应机理。构建集温度响应、分子识别、荧光传感和磁性分离功能于一体的新型传感体系，以期实现对食品中双酚A的快速、灵敏、高选择性检测。该研究将为多功能智能荧光材料的开发及荧光传感体系的构建提供理论基础和方法借鉴，对促进食品检测技术发展、保证食品安全具有重要意义。

双酚A是一种极具代表性的内分泌干扰物，工业上常用于合成各种高分子材料，上世纪60年代开始被广泛应用于食品相关容器及包装材料的生产，后续研究发现存在双酚A从接触材料向食品中迁移问题。而作为双酚A的替代物，双酚AF、双酚B、双酚F、双酚S等双酚类化合物近年来也被证实具有不同程度的毒性和雌激素样效应，引发了社会各界对于双酚类化合物残留问题的广泛关注。为对食品中双酚A及其化合物迁移量进行准确评价分析，发展高效、高灵敏的检测方法具有重要意义。. 本研究将荧光检测技术的高灵敏性和分子印迹技术的高选择性相结合，开发了基于碳点-分子印迹聚合物的复合荧光材料，并通过温敏单体和磁性纳米材料的引入，构建了环境刺激响应型荧光探针，实现了复杂基质中双酚A的高选择性快速荧光检测。此外，开发了3种高效吸附材料，结合常规液相色谱分析，建立了高选择性色谱分析技术。形成了双酚A高灵敏度、高选择性分析检测技术体系。采用计算机模拟技术，获得了分子印迹聚合物的准确结构信息，明确了对目标物的相互作用机制，结合吸附性能实验结果，阐明了印迹位点主导下的专一性分子识别机理。. 本研究为复合荧光探针的构建和新型吸附材料的开发提供了策略，为食品中小分子污染物的精准检测和有效控制提供了理论基础和技术支持。