采用新型分子表面印迹技术构建手性空穴实现对氨基酸对映体识别拆分的研究

Constituting Chiral Caves by Using Novel Surface-Molecular Imprinting Technique and Realizating Chiral Separation of Enantiomers of Amino Acid

通过γ-(甲基丙烯酰氧)丙基三甲氧基硅烷的媒介,在溶液聚合体系中,采用"接出"("graft from")法将功能单体甲基丙烯酸二甲基氨基乙酯(DMAEMA)接枝于硅胶微粒表面,制得了功能接枝微粒PDMAEMA/SiO2,采用本课题组建立的新型分子表面印迹技术,以天冬氨酸(Asp)的一种对映体L-Asp为模板分子,二氯乙醚为交联剂,对接枝在硅胶表面的大分子PDMAEMA实施了分子印迹,制备了L-Asp分子表面印迹材料MIP-PDMAEMA/SiO2.以天冬氨酸的另一种对映体D-Asp为对比物,采用静态与动态两种方法深入研究了MIP-PDMAEMA/SiO2对L-Asp分子的识别性能,重点探索了采用分子表面印迹材料对氨基酸对映体进行拆分的可行性.实验结果表明,印迹材料MIP-PDMAEMA/SiO2对模板分子L-Asp具有良好的识别选择性与结合亲和性,相对于D-Asp,识别选择性系数为3.24,显示出良好的拆分性能.此外,印迹材料MIP-PDMAEMA/SiO2也具有良好的解吸性能,以稀NaOH水溶液作为洗脱液,13个床体积内解吸率即可达到99.73%.

Dimethylaminoethyl methacrylate（DMAEMA） was grafted on micron-sized silica gel particles in a manner of ＂graft from＂ in a solution polymerization system by right of the mediation action of the cou-pling agent 3-methacryloxypropyl trimethoxysilane（MPS）,obtaining the grafted functional particles PDMAEMA/SiO2.Then,the molecular imprinting towards the grafted PDMAEMA was performed with L-Asp that is one enantiomer of aspartic acid（Asp） as template molecule and dichloroether as crosslinking agent by using the novel surface-molecular imprinting technique established by our research group,and the L-Asp molecule-imprinted material MIP-PDMAEMA/SiO2 was prepared.Both static and dynamic methods were adopted to study the recognition property of MIP-PDMAEMA/SiO2 particles for L-Asp with respect to another enantiomer of aspartic acid,D-Asp,and the separation ability towards L-Asp and D-Asp in the ra-ceme.The experiment results show that MIP-PDMAEMA/SiO2 particles possess obvious recognition selec-tivity and fine binding affinity for L-Asp,and the selectivity coefficient is equal to 3.24.Besides,MIP-PDMAEMA/SiO2 particles have excellent elution property,and with a diluted aqueous solution of NaOH as the eluent,the desorption ratios of L-Asp reach 99.73% in 13 BV.