离子对电色谱法分离机理的理论探讨

Separation Mechanism of Ion-pair Electrochromatography

离子对电色谱是离子对高效液相色谱与电泳模式的复合体 ,兼具两种方法的特点 ;作者基于计量模型的基本假设 ,并考虑溶质在电色谱过程中的输运机制 ,通过对溶质在柱过程中涉及的多种平衡过程进行考察 ,得到了可以说明溶质迁移速率随离子对试剂浓度和各种相互作用之间关系的理论表达式 ;以中性溶质和简单带电溶质为例 ,对理论迁移方程进行简化 ,结果表明带电溶质在离子对电色谱中的迁移过程同时受色谱机理、离子对作用和电泳分离机理的影响 ,因此离子对电色谱对样品溶质应有更好的选择性 。

Ion _ pair electrochromatography(IPCEC) is a hybrid of CE and ion _ pair HPLC having the advantages of the two methods. Considering the transfer of the different conjugate solutes and equilibria between them in column, an expression was theoretically derived based on the metrology model, which describes the change of the apparent transfer speed of solute due to the concentration of ion _ pair reagent and the speed of the conjugates of solute. For neutral solute and common dissolvable solute, the expression can be simplified. The results showed that the transfer speed should be sumultaneously effected by the mechanism of chromatography and electrophoresis as well as ion _ pair interaction in ion _ pair electrochromatography. This separation mode will improve the selectivity of the solutes in sample and be suitable for fast separation.