Hu Shao-Qiang, Wang Gui-Xia, Guo Wen-Bo, Guo Xu-Ming, Zhao Min
College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022, China.
College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022, China.
J Chromatogr A. 2014 May 16;1342:86-91. doi: 10.1016/j.chroma.2014.03.042. Epub 2014 Mar 24.
The effect of low concentrations of sodium dodecyl sulfate (SDS) on the separation of palonosetron hydrochloride (PALO) stereoisomers by micellar electrokinetic chromatography (MEKC) has been investigated. It was found that the addition of SDS prolongs the migration time and the migration order of four stereoisomers changes regularly with the SDS concentration. Good separations for all the four stereoisomers were achieved at appropriate SDS concentration. The effect of SDS on the electromigration (mobilities) of PALO stereoisomers has been studied, in order to explain its effect on the separation by MEKC. It was found that low concentrations of SDS added into the separation media forms negatively charged complexes with PALO stereoisomers and hence reverses their electromigration direction. Furthermore, the migration order between two enantiomeric pairs is also reversed because the enantiomeric pair with a bigger positive mobility than that of another pair turns to have a bigger negative mobility when bound with SDS. Based on these results, the effect of SDS on the MEKC separation of PALO stereoisomers was elucidated reasonably. The performance of the developed chiral MEKC method was validated by the analysis of a real sample.
研究了低浓度十二烷基硫酸钠（SDS）对胶束电动色谱（MEKC）分离盐酸帕洛诺司琼（PALO）立体异构体的影响。发现加入SDS会延长迁移时间，且四种立体异构体的迁移顺序随SDS浓度有规律地变化。在合适的SDS浓度下，所有四种立体异构体都实现了良好的分离。研究了SDS对PALO立体异构体电迁移（迁移率）的影响，以解释其对MEKC分离的作用。发现向分离介质中加入低浓度的SDS会与PALO立体异构体形成带负电荷的络合物，从而使其电迁移方向反转。此外，两个对映体对之间的迁移顺序也发生了反转，因为与另一对相比具有更大正迁移率的对映体对在与SDS结合时会变成具有更大负迁移率。基于这些结果，合理地阐明了SDS对PALO立体异构体MEKC分离的影响。通过对实际样品的分析验证了所建立的手性MEKC方法的性能。
