【作者】 刘芳华；

【导师】 叶建农；

【作者基本信息】 华东师范大学 ， 分析化学， 2005， 硕士

【摘要】 毛细管电泳具有分离效率高、快速和所需样品量少等特点。应用范围包括无机离子、有机分子及生物大分子和对映体等,在分析化学、生物化学、分子生物学、药物化学、食品化学、环境化学和医学许多领域,有着广阔的应用前景。在绪论中回顾了毛细管电泳（CE）的历史、现状和发展趋势,对毛细管电泳的基本原理和特点进行了简单的介绍,并详细的介绍了毛细管电泳-电化学检测技术（CE-ED）以及毛细管电泳-电化学检测在中药和食品分析中的应用。本文采用毛细管电泳-电化学检测技术测定了中药和食品中的生物活性成分,如黄酮和多酚等,拓展了毛细管电泳-电化学检测的应用范围。主要研究内容如下: 1.毛细管电泳电化学检测法测定荞中的多酚 荞麦是一种极具营养价值的食品,富含维生素B₁、B₂和多种氨基酸,而且含有多种抗氧化活性成分,如维生素E和多种酚类物质。这些多酚类物质有芦丁和酚酸及其衍生物等。采用毛细管电泳-电化学检测法同时测定了荞麦皮和荞麦粉中表儿茶素、芦丁、金丝桃甙和槲皮素的含量。考察了电极电位、运行缓冲液的酸度和浓度、电泳电压及进样时间对分离和检测的影响。在最佳实验条件下,以300μm直径的碳圆盘电极为检测电极,检测电位为+0.90V（vs.SCE）,在50mmol/L硼酸盐（pH∶8.7）的运行缓冲液中,上述各组分在20min内能完全分离。被测物浓度与峰电流在三个数量级范围内呈良好线性,检测限在1×10^-7g/ml-5×10^-7g/ml之间,该法简单可靠,已经成功地应用于荞麦多酚的测定。 2.毛细管-电泳电化学检测法测定金银花中的有效成分 金银花（Lonicera japonica Thumb.）,又名忍冬,为临床常用中药,具有清热解毒,凉散风热之功效。采用毛细管电泳-电化学检测法同时测定了金银花中的金丝桃甙、绿原酸、木犀草素和咖啡酸的含量,并比较了不同产地金银花中上述组分的含量差别。考察了电极电位、运行缓冲液的酸度和浓度、电泳电压及进样时间对分离和检测的影响。在最佳实验条件下,以300μm直径的碳圆盘电极为检测电极,检测电位为+0.90V（Vs.SCE）,在50mmol/L硼酸盐（pH∶8.7）的运行缓冲液中,上更多还原

【Abstract】 The history, the current situation and the future trend of capillary electrophoresis （CE） is reviewed. CE is becoming increasingly recognized as an important analytical separation technique due to its speed, efficiency, reproducibility, ultra-small sample volume, and ease of clearing up the contaminants. CE has been widely applied in many fields. In combination with electrochemical detection （ED）, CE-ED offers high sensitivity and good selectivity for electroactive species. The present thesis described the studies of CE-ED application in the analyses of foods and traditional Chinese medicines. The major content is described as follows:1. Determination of phenolic compounds of buchwheat （Fagopyrum esculentum Moench） hulls and flour by capillary electrophoresis with electrochemical detectionA simple, reliable and reproducible method, based on capillary electrophoresis with electrochemical detection （CE-ED）, for the determination of phenolic compounds of buckwheat （Fagopyrum esculentiim Moench） hulls and flour was reported. The active ingredients mainly consist of （-）-epicatechin, rutin, hyperoside and quercetin. Operated in a wall-jet configuration, a 300 μm diameter carbon disk electrode was used as the working electrode, which exhibits good response at +0.90 V （vs. SCE） for all analytes. The effects of potential of working electrode, pH and concentration of running buffer, separation voltage and injection time on CE-ED were investigated. Under the optimum conditions, the analytes could be separated in a 50 mmol/L borate buffer （pH=8.7） within 20 min. The response was linear over three orders of magnitude with detection limit （S/N=3） ranging from 2*10^-7 g/mL to 5*10^-7 g/mL for all analytes. This method has been used for the determination of phenolic compounds of buchwheat （Fagopyrum esculentiim Moench） hulls and flour, and the assay result was satisfactory.2. Determination of active ingredients of Lonicera japonica Thumb, by capillaryelectrophoresis with electrochemical detectionCapillary electrophoresis with electrochemical detection was employed to analyse active ingredients of Lonicera japonica Thumb., an important crude herb frequently used in Chinese medicines. Hyperoside, chlorogenic acid, luteolin and caffeic acid are major important active ingredients. Operated in a wall-jet configuration, a 300-μm diameter carbon-disk electrode was used as the working electrode, which exhibits a good response at +0.90 V （vs. saturated calomel electrode） for four analytes. Under the optimum conditions, the analytes were baseline separated within 20 min in a 50 mmol/1 borax buffer （pH 8.7）. Notably, excellent linearity was obtained over two orders of magnitude with detection limits （S/N） ranging from 1*10^-7 g/ml to 5*10^-7 g/ml for all the analytes. This method was successfully used in the analysis of Lonicera japonica Thumb, with relative simple extraction procedures, and the assay results were satisfactory.3. Determination of the bioactive flavonoids from rhododendron dauricum L. by capillary electrophoresis with electrochemical detectionA simultaneous determination of bioactive flavonoids from Rhododendron dauricum L. by capillary electrophoresis with electrochemical detection （CE-ED） was reported. The effects of potential of working electrode, pH and concentration of running buffer, separation voltage and injection time on CE-ED were investigated. Under the optimum conditions, the analytes could be separated in a 70 mmol/L borate buffer （pH=9.2） within 20 min. A 300 μm diameter carbon disk electrode has a good response at +0.90 V （vs. SCE） for all analytes.The response was linear over three orders of magnitude with detection limit （S/N=3） ranging from 2*10^-8 g/mL to 2* 10^-7 g/mL for all analytes. This method has been used for the determination of these analytes in Rhododendron dauricum L. after a relative simple extraction procedure, and the assay result was satisfactory.更多还原