流动注射-毛细管电泳联用技术构建的微流体系研究

报道了一种将流动注射和毛细管电泳联用的简单、快速、可连续进样的微流体系,该微流体系是用商用毛细管和常规分析实验室易得材料构建,双T构型的微流体系设计是水平分离通道为内径75μm×146 mm(有效分离长度93 mm)的石英毛细管,毛细管两端由内径0.5 mm的泵管垂直引出,毛细管镶嵌在22 mm×6 mm×3 mm的有机玻璃基片上,考察了中药样品中的活性组分麻黄碱和伪麻黄碱在双T构型微流体系上的分离行为,比较了流动注射分析仪的两种进样模式,在pH9.50的15mmol/L硼砂缓冲溶液、检测波长215nm、电场强度137V/cm的条件下,3min内可获得麻黄碱和伪麻黄碱的基线分离,连续导入一系列样品的进样频率是49 h-1(最大值59 h-1),基于以上实验结果,推导出了计算微流体系进样频率的一种简单的经验公式.

Manipulation and characterization of a micro-fluidic system based on capillary electrophoresis coupling to flow injection

A simple,rapid and continuous micro-fluidic system based on capillary electrophoresis coupling to flow injection was presented. The micro-fluidic system was produced using commercial capillary and components readily available in the analytical laboratory. In a double-T configuration,the designed horizontal separation channel was a 75μm I.d.×146 mm(an effective separation length of 93 mm) quartz capillary,with two vertical elicitation arms produced from 0.5 mm I.d. Plastic tubing. Capillary was embedded in 22 mm×6 mm×3 mm organic glass base. Using the double-T configuration,ephedrine and pseudo-ephedrine,active components of some traditional Chinese medicine was used to investigate the separation behavior of this system. Two injection modes of flow injection analyzer were compared for obtaining the higher separation efficiency. Baseline separation of ephedrine and pseudo-ephedrine was achieved at 215 nm in 15 mmol/L borate buffer(pH 9.50) about 3 min,at electrical field strength of 137 V/cm. Continuous introduction of a series of samples was achieved at 49 h-1 throughout (the maximal value was 59 h-1). Based on these experimental results,a simple and general empirical rule for totally calculating the sampling in this system was developed.