聚合离子液体用作毛细管电泳背景电解质添加剂快速高效分离5种核苷类化合物

将聚乙烯基-3-乙基咪唑溴盐离子液体用作毛细管电泳背景电解质添加剂，利用聚合离子液体的阳离子聚合物性质静电吸附到毛细管内表面，成功实现电渗流的有效反转，建立了共电渗流模式下5种核苷类化合物分离的新方法。考察了聚合离子液体浓度、pH值等因素对电渗流的影响。在优化实验条件下，3.1 min内实现了对5种核苷类化合物的快速高效分离；将该方法分别与不加添加剂和加入离子液体单体后的体系进行对比，结果表明，该方法大大缩短了5种核苷类化合物的分析时间，提高了分析效率，最高柱效达95万/m塔板数，分析物的迁移时间RSD均不高于0.38%。该方法简单、快速、重复性好，具有很好的应用前景。

High Speed and Efficient Separation of 5 Nucleosides by Capillary Electrophoresis Using Polymeric Ionic Liquid as Background Electrolyte Modifier

A novel and easy method was developed for the separation of 5 nucleosides by capillary electrophoresis in co-electroosmotic mode using a polymeric ionic liquid(PIL),poly(1-vinyl-3-ethylimidazolium bromide) as background electrolyte modifier.The polymeric ionic liquid,as a cationic polymer,was electrostatically attached to the negatively charged surface of the fused-silica capillary,generating a reversed electroosmotic flow.Effects of polymeric ionic liquid concentration and pH on the electroosmotic flow were studied.Effects of several factors such as background electrolytes(BGES) concentration and pH value on separation were also investigated.Under the optimized conditions,good separation of 5 nucleosides was achieved with high column efficiency and excellent reproducibility in 3.1 min.Meanwhile,the method was compared with capillary electrophoresis background electrolyte system without or with ionic liquid(IL or PIL)as additive.The results showed that the separation time of 5 nucleosides was reduced sharply and the separation efficiency was improved after adding PIL.The highest column efficiency was up to 950 000 plates/m.RSDs(n=5) of the migration time for the analytes were all no more than 0.38%.The method is simple,efficient and excellently reproducible and has a good application prospect.