水产品中无机砷选择性分离的咪唑类离子液体@金属有机框架材料的可控构筑及机理研究

There is rare data on selective separation of inorganic arsenic in aquatic products by metal organic frameworks (MOFs) adsorbent loaded with imidazole based ionic liquids (IIL) because no relative reports has been published till now. In this proposal, a series of imidazole based ionic liquid loaded metal organic frameworks (IIL@MOFs) materials will be prepared from different IIL and MOFs materials using strring synthesis method. Following the process of selective separation is studied. IIL@MOFs will be prepared successfully according to the selective adsorption capacities of inorganic arsenic, and then reveal the relationship between the mircro-scale parameters of IIL@MOFs and selective adsorption properties and adsorption capacities. The selective adsorption kinetics and thermodynamics of inorganic arsenic will be also investigated by static and dynamic adsorption experiments respectively to clarify the mechanism of selective adsorption. Finally, solid phase extraction technology will be adopted base on IIL@MOFs to separate inorganic arsenic in aquatic products followed by hydride generation atomic fluorescence spectrometric quantification. The goal of this proposal is to establish a simple, low-cost, highly sensitive, and highly selective inorganic arsenic detection method, and provide basic data on preparation and application of new material for selective separation of inorganic arsenic in food. In a word, the implementation and conduction of this program will be of great theoretical and practical significance.

国内外尚未见咪唑类离子液体负载金属有机框架材料(IIL@MOFs)用于水产品中无机砷选择性分离的研究报道，基础数据相对缺乏。本项目采用化学嫁接法制备出系列IIL@MOFs材料，研究其选择性分离无机砷过程，筛选并构筑出无机砷高选择性、强富集能力的IIL@MOFs材料，揭示其结构的微尺度调控与无机砷选择性分离的构效关系，明确其无机砷选择性吸附动力学和热力学，阐明选择性分离机理，并构建基于IIL@MOFs材料的固相萃取体系，实现水产品中无机砷高选择性、高灵敏度、低成本、易操作的分离分析。该项目的实施和开展将对水产品中无机砷选择性分离新材料的制备及其应用研究提供一定的基础数据，具有重大的理论和实践探索意义。

砷的毒性不仅与总量有关，更取决于形态，无机砷（As3+、As5+为主）的毒性要比有机砷高100多倍，并主要通过食物链直接或间接危害人类健康甚至生命，已成为当前食品安全中重点监控的化学残留物之一。设计和制备具有高选择性、强富集能力的萃取材料是实现无机砷高灵敏度分析检测的关键。本项目通过将具有阴离子交换能力及表面带正电荷等双重特性的1-甲基咪唑离子（1-MIIL）、氨基咪唑离子液体（ABIL-Br）修饰到比表面积大、易修饰的介孔分子有机材料SBA15和金属有机框架材料HKUST-1上，构筑出无机砷高选择性、强富集能力的萃取材料，实现了该材料在水产品及食品中无机砷高选择性、高灵敏度的测定（LOD<10 ng/g，RSD<2%，回收率90-105%之间），该研究结果可为食品中无机砷选择性分离分析提供科学依据，也为无机砷国家安全标准的制定或完善提供新的参考和借鉴。