Shanghai Key Laboratory of Functional Materials Chemistry, East China University of Science and Technology, Shanghai 200237, PR China.
Talanta. 2013 Jan 30;104:173-9. doi: 10.1016/j.talanta.2012.11.021. Epub 2012 Nov 16.
Novel open-tubular capillary electrochromatography (OT-CEC) systems with core/shell magnetic nanoparticles modified by amino or C18 groups as stationary phase were constructed by immobilizing nanoparticles in the capillary with permanent magnets. Influence of preparation method of OT-CEC column with series stationary phases (continuous two-dimension) on column performance and effect of dispersant on capability of OT-CEC column prepared by stationary phases with mixed functionalities (mixed stationary phases) were investigated in details to achieve stable preparation. Organic acids were used to evaluate the OT-CEC systems, and the relative column efficiency of salicylic acid was 420,000 plates/m for series stationary phases, while that of benzoic acid reached 480,000 plates/m for mixed stationary phases. The excellent within-column and between-column repeatability (n=5) testified with the RSDs of retention time were less than 0.44% and 10.20% for series stationary phases and 1.65% and 4.29% for mixed stationary phases. The two OT-CEC systems were further applied to separation of the aqueous extract of Rhizoma gastrodiae. Comparing with normal OT capillary column, the new systems show extra high column efficiency due to large surface areas of nanoparticles and multiple separation mechanisms, and they have great potential in the method development for the analysis of complicated samples.
新型开放式管状毛细管电色谱（OT-CEC）系统，采用氨基或 C18 基团修饰的核/壳磁性纳米粒子作为固定相，通过将纳米粒子固定在毛细管内的永久磁铁上进行构建。详细研究了具有系列固定相（连续二维）的 OT-CEC 柱的制备方法对柱性能的影响，以及分散剂对具有混合功能固定相（混合固定相）制备的 OT-CEC 柱性能的影响，以实现稳定的制备。采用有机酸来评价 OT-CEC 系统，对于系列固定相，水杨酸的相对柱效达到 420,000 板/m，而对于混合固定相，苯甲酸的柱效达到 480,000 板/m。出色的柱内和柱间重复性（n=5），保留时间的 RSD 小于 0.44%和 10.20%，对于系列固定相和 1.65%和 4.29%，对于混合固定相。这两个 OT-CEC 系统进一步应用于天麻根茎提取物的分离。与普通 OT 毛细管柱相比，由于纳米粒子的大表面积和多种分离机制，新系统表现出额外的高柱效，它们在分析复杂样品的方法开发方面具有很大的潜力。
