新型亚微米亲水作用色谱的制备及其在加压毛细管电色谱中的应用

采用改良Stöber法合成580 nm亚微米单分散的二氧化硅微球，并以此为基质，通过"巯基-烯"点击化学反应将半胱氨酸成功键合到修饰有乙烯基团的二氧化硅微球表面，合成了一种新型亚微米亲水作用固定相（Cys-VTMS-SiO₂）。采用高压匀浆法制备了新型亚微米亲水色谱填充柱，通过不同乙腈比例、缓冲盐浓度和pH条件下对甲苯、丙烯酰胺和硫脲的分离分析揭示其亲水机理。依托加压毛细管电色谱平台，成功实现了对核苷、酚类、胺类及多肽等亲水性物质的快速有效分离，其有望应用于其他强极性和亲水性化合物的分离分析。

Preparation and characterization of a novel hydrophilic stationary phase and its application in pressurized capillary electrochromatography

Silica particles having different sizes were synthesized by a modified Stöber method. The reaction temperature, stirring rate, and time conditions were optimized. Finally, 580 nm monodispersed silica particles were synthesized. Moreover, a novel zwitterionic stationary phase with strong hydrophilicity was prepared based on a "thiolene" click reaction between cysteine and the silica particles modified vinyl group (Cys-vinyltrichlorosilane (VTMS)-SiO₂). A column packed with submicron cysteine-bonded silica was prepared by the slurry packing method. The hydrophilic mechanism was revealed by the separation of toluene, acrylamide, and thiourea using different ratios of acetonitrile. The effects of applied voltage, buffer concentration, and buffer pH on the separation ability of the capillary column packed with 580 nm Cys-VTMS-SiO₂ were examined to achieve optimal results. In addition, the run-to-run and day-to-day reproducibilities in terms of retention time and peak area for the above mentioned compounds were both 2.0%. The good batch-to-batch reproducibility indicated that the preparation method was suitable for the fabricated column. The column used in the pressurized capillary electrochromatography (pCEC) system demonstrated efficient and fast separation of a mixture consisting of nucleosides, phenols, amines, and peptides after the optimization of the separation condition. The proposed method shows good potential for the separation of polar and hydrophilic compounds.