高选择性和高排阻限进材料的可控构建及其对食品污染物萃取检测一体化方法研究

限进吸附剂具有排除蛋白质等大分子干扰的同时萃取小分子的双重功能，能够直接应用于食品等样品中小分子的富集，简化样品处理步骤。然而，现有限进材料的吸附选择性和大分子排阻性能亟待提高。本项目采用表面引发原子转移自由基聚合（SI-ATRP）技术，依照分子结构匹配单体类型在硅胶表面构筑多功能基共聚物吸附层，继而再采用SI-ATRP构筑两性离子聚合物限进层，制备新型限进材料。以蛋白溶液中的抗生素药物为富集对象，调控吸附层的共聚物结构与限进层的亲水性结构，探究对药物分子的富集性能、识别机制、吸附选择性和对蛋白质的排阻性能，明确共聚物结构与吸附选择性、两性离子聚合物与排阻作用间的构效关系，为开发高选择性和高排阻限进吸附剂提供理论指导；建立基于限进吸附剂的固相萃取柱偶联液质的集高效萃取与检测为一体的在线分析，用于对食品中痕量污染物的直接进样检测，阐明新型限进材料在快速、准确分析复杂样品中的应用价值。

Restricted access sorbents have the dual function of removing the interference of macromolecules such as protein and extracting small molecules. It can be directly extract small molecules in food samples to simplify the pretreatment process. However, its extraction selectivity to small molecules and exclusion properties to macromolecules (e.g., proteins) should be improved. This project selects two or three functional monomers, which match the structure of the object, to graft copolymers on the surface of silica nanoparticles to construct multifunctional polymer adsorption layer by the surface-initiated atom transfer radical polymerization (SI-ATRP), and then the zwitterionic polymers are immobilized via the second SI-ATRP to construct restricted access layer, obtaining a new type of the restricted access sorbents. Using antibiotic drugs in protein solution as the enrichment object, the extraction properties, recognition mechanism and adsorption selectivity of drug molecules as well as exclusion properties of protein will be explored by regulating the copolymer structure of the adsorption layer and the hydrophilic structure of the restricted layer, clearing structure-effective relationship between copolymer structure and adsorption selectivity as well as zwitterionic polymer and exclusion effect. The project can provide theoretical guidance and experimental support for the development of restricted access materials with high selectivity and high exclusion. The online analysis of solid phase extraction column based on restricted access adsorbents in conjunction with LC/MS will be established to directly injected detection of trace antibiotics in food using the integrated method of high-efficiency extraction and detection, the application prospects of new magnetic restricted access sorbents will be elucidated in rapid and accurate analysis of complex samples.