金属离子介导的L-色氨酸印迹整体柱制备及其性能评价

Preparation and evaluation of L-tryptophan imprinted monolithic column mediated by metal ion

采用金属离子介导策略,以L-色氨酸为模板分子、Pb^2+为介导离子、甲基丙烯酸为功能单体、乙二醇二甲基丙烯酸酯为交联剂、乙醇-水为致孔剂采用原位热聚合法制备了新型的氨基酸印迹整体柱。结果显示,模板-功能单体-交联剂的最佳比例为1∶4∶20,获得的印迹整体柱最大柱效为N=7020 m^-1,最大印迹因子(IF)为12. 4,明显大于不加Pb^2+的印迹整体柱(IF=2. 3)。在最佳色谱条件下,L-色氨酸在3. 06×10^-11~9. 79×10^-4mol/L浓度范围内线性良好(y=3,819×10^6x+0. 30,R^2=0. 9999),重复进样峰面积的RSD为2. 4%,连续使用30 d后色谱柱的柱效没有明显变化,表明此新型印迹整体柱可以用于L-色氨酸的常量及微量分析。

In order to enhance the imprinting effect of amino acid, the strategy of mediation by metal ion was adopted in this paper. L-tryptophan was used as template molecule, Pb^2 + as mediated ion, methacrylic acid as functional monomer, ethylene glycol dimethacrylate as cross-linker, ethanol - water as porogen to synthesize a novel amino acid imprinted monolithic column by in situ thermal polymerization. The results displayed that the optimum ratio of template - functional monomer - crosslinker was 1 :4: 20. The best column efficiency of the obtained imprinted monolith was 7020 m^-1 and the maximum imprinting factor (IF) was 12.4, which was significantly larger than that of imprinted monolith without adding Pb^2+(IF = 2. 3 ). Under the optimal chromatographic conditions, the target analyte of L-tryptophan had a good linear in the concentration range of 3. 06×10^-11 - 9. 79 × 10^-4 mol/L on the obtained imprinted monolith (y = 3. 819 × 10^6x + 0. 30, R^2 = 0. 9999 ). The RSD of peak area with repeated injection was 2. 4%, and the column efficiency had no obvious change with the use of 30 consecutive days. In conclusion, this report developed a new type of molecularly imprinted monolithic column which could be used for the constant and trace analysis of L-tryptophan.