Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China.
Ministry of Education Key Laboratory of Laser Life Science & Institute of Laser Life Science, College of Biophotonics, South China Normal University, Guangzhou 510631, China.
J Chromatogr A. 2020 Jul 5;1622:461147. doi: 10.1016/j.chroma.2020.461147. Epub 2020 May 6.
Molecularly imprinted polymers coated magnetic particles (FeO@MIPs) were prepared and used as adsorbents in solid phase extraction for efficient enantioseparation of racemic tryptophan (Trp) in aqueous medium. The amino-modified magnetic particles (FeO-NH) were first synthesized by one-pot hydrothermal method. Then the template molecules (L-Trp) were assembled on the surface of FeO-NH. Finally, FeO@MIPs were prepared via a sol-gel method using L-Trp@FeO-NH complex as matrix, 3-aminopropyltriethoxylsilane and n-octyltriethoxysilane as functional monomers. The as-prepared FeO@MIPs were spherical with an average diameter about 149 ± 6.0 nm. The thickness of MIPs layer was approximately 3.5 ± 2.3 nm. The adsorption isotherms data of FeO@MIPs toward L-Trp and D-Trp were well described by the Langmuir model. The maximum adsorption capacities of FeO@MIPs for L-Trp and D-Trp were calculated to be 17.2 ± 0.34 mg/g and 7.2 ± 0.19 mg/g, respectively. The material exhibited good selectivity toward L-Trp with imprinting factor of 5.6. Excitingly, the enantiomeric excess (ee) of Trp in supernatant after adsorption of racemic Trp by FeO@MIPs was as high as 100%. The result suggests that the imprinted caves in FeO@MIPs are highly matched with L-Trp molecule in space structure and spatial arrangement of active functional groups. The work also demonstrates that sol-gel technology has great potential in preparation of MIPs for chiral separation.
磁性分子印迹聚合物纳米微球（FeO@MIPs）被制备并用作固相萃取中的吸附剂，以在水介质中高效对映选择性分离外消旋色氨酸（Trp）。首先通过一锅水热法合成氨基修饰的磁性粒子（FeO-NH）。然后将模板分子（L-Trp）组装在 FeO-NH 的表面上。最后，通过溶胶-凝胶法使用 L-Trp@FeO-NH 复合物作为基质，3-氨丙基三乙氧基硅烷和正辛基三乙氧基硅烷作为功能单体，制备了 FeO@MIPs。所制备的 FeO@MIPs 呈球形，平均直径约为 149±6.0nm。MIPs 层的厚度约为 3.5±2.3nm。FeO@MIPs 对 L-Trp 和 D-Trp 的吸附等温线数据很好地用朗缪尔模型描述。FeO@MIPs 对 L-Trp 和 D-Trp 的最大吸附容量分别计算为 17.2±0.34mg/g 和 7.2±0.19mg/g。该材料对 L-Trp 表现出良好的选择性，印迹因子为 5.6。令人兴奋的是，在通过 FeO@MIPs 吸附外消旋 Trp 后，上清液中 Trp 的对映体过量（ee）高达 100%。结果表明，FeO@MIPs 中的印迹空穴在空间结构和活性功能基团的空间排列上与 L-Trp 分子高度匹配。该工作还表明，溶胶-凝胶技术在制备手性分离用 MIPs 方面具有巨大的潜力。
