基于离子印迹固相萃取分离和富集海水痕量金属元素自动快速监测新方法研究

In order to resolve difficult problems including strong matrix interference in determination of heavy metals in sea water and online simultaneous multi-element analysis, a novel method of ion imprinted solid phase extraction (IISPE) is presented and has been applied to sea water sample pretreatment. When IIPs are applied to pretreatment for aqueous phase systems, like environmental samples, the identification procedure can be interfered by the solvent and as a result, imprinting and recognition become difficult. The presented method uses highly selective metallo-chelate as the template, Contemplated synthesis of amino-functionalized mesoporous silica particles as the solid phase extraction packing and covalently bonded the ion-imprinted polymers to the pores of the mesoporous silica particles，and obtains the filler that has large adsorption capacity and selectivity for heavy metal ions. The new type of solid phase extraction column made in this way removes the critical technical barrier of sea-water sample pretreatment, accomplishes the imprinting and recognition of metal ions in sea water. It significantly improves the efficiency of separation and preconcentration for metal elements in sea water. It can be combined with metal mass spectrometry，remove the matrix effect of sea-water, improve the sensitivity of the sea-water heavy-metal measurement system, and realize online separation/preconcentration and simultaneous multi element analysis of sea-water heavy metals. The presented method establishes the foundation for fast on-field automated analysis of sea-water trace elements.

针对海水痕量金属元素检测过程中待测元素浓度极低，基体干扰严重、难以在线多元素同时分析等技术难题，本项目拟开发以氨基功能化介孔二氧化硅为载体的新型离子印迹固相萃取技术（IISPE），构建集纯化、分离和富集于一体的快速自动、高通量海水样品预处理技术，并对该技术进行测试和优化。对介孔二氧化硅进行氨基功能化，得到单分散性、比表面大、孔道规则、孔径可调、稳定性好的载体，将乳液聚合方式合成的离子印迹聚合物共价键合到载体粒子孔道中，制得高选择性金属离子富集填料并进行装填，研制特异吸附铜、铅、锌、镉、铬离子的固相萃取柱，并对其吸附特性、使用寿命等系统分析，发展用于海洋环境体系的离子印迹固相萃取新方法，结合便携式重金属元素在线分析仪，建立一种同时对海水中五种重金属元素快速、高效分离和富集的新方法。该项目开展将为海水重金属多元素同时快速在线监测提供一种新方法，对提高我国海洋环境监测技术水平具有重要意义。

（1）本文采用APTES、TEOS、MTMS三种硅烷化合物作为反应物，通过溶胶-凝胶法合成氨基功能化介孔二氧化硅材料。结果表明，该材料具有较高的比表面积和孔体积，三维孔道结构对重金属离子铅离子、铜离子等的吸附和去除率较之未氨基功能化的材料明显提高，初步表明氨基功能化介孔二氧化硅可作为重金属离子的选择性吸附载体。（2）本文以铜离子为模板离子，环氧丙烷为交联剂，在氨基功能化介孔二氧化硅孔壁表面制得了铜离子印迹聚合物，由于该材料具有比表面积大，印迹空穴的孔道较浅等特点，铜离子的扩散阻力小，能快速与结合位点相结合，对铜离子具有很强的亲和性和优良的吸附选择性，对锌离子和镉离子也具有一定的吸附性，较之铜离子吸附性能差些。结合在IIP- PEI/SiO2上的离子洗脱性能良好，有利于印迹材料的再生与利用。（3）将离子印迹技术应用于海水中重金属元素的分离和富集，制备具有优越的识别性、预定性及实用性，可以专一识别水溶性分子、金属离子的离子印迹聚合物填料。离子印迹固相萃取柱的研制及建立一种用于复杂海水体系中的离子印迹聚合物特异性吸附、分离的固相萃取新方法。