| Capillary electrophoresis (CE) is a new-type, efficient and rapid technique in the area of liquid-phase separations. The separation principle is based on the phenomena that ionized molecules of different mass/charge ratios will travel with different velocities under the force of a high-voltage electric field through a fused silica capillary. The analytes can be separated and then detected by the detector due to their different velocities. Owing to its high separation efficiency, fast analyzing speed, less sample consumption, easiness to automate, less solvent consumption and environmental friendliness, CE has been widely applying in many areas such as chemical analysis, biomedical sciences, food science, and environmental analysis etc. There are many types of detector applied to CE. Amperometric detection (AD) is one of Electrochemical detections which has many advantages over other widely used techniques. AD provides good selectivity and high sensitivity, and is much more economical, without complicated pretreatment procedure, so it has been used to various areas. For the sake of enhancing the detection sensitivity and broadening its application areas, we mainly focus on the simultaneous separation and detection of active substances in chrysanthemum and Blueberry wine using CE-AD.This paper is composed of three chapters. The first chapter is a brief introduction of CE, including history and background, separation principle, sample injection and separation models, detection techniques, application areas, study situation, as well as the objective and meanings of this paper.In chapter two, a high-performance capillary electrophoresis with amperometry detection method (CE-AD) has been developed for the analysis of flavonoids and anthraquinones (emodin, kaempferol, apigenin, luteolin and rhein) in chrysanthemum. The factors affecting the CE separation, such as working potential, pH value and concentration of running buffer, separation voltage and sample injection time were investigated. Under the optimum conditions, these five analytes were base-line separated within 17 min using a borate-phosphate running buffer (3×10-2 mol of borate-phosphate, pH 9.0) at a separation voltage of 19 kV. Operated in a wall-jet configuration, a 300μm diameter carbon-disk electrode was used as the working electrode, which exhibited good current responses at+0.90 V (vs. SCE) for the five analytes. The linear relationship between concentration and current response was obtained with detection limits (S/N=3) ranged from 1.0×10-7 to 2.1×10-7 g/mL for all analytes. This proposed method was successfully used in the analysis of four kinds of chrysanthemum with relatively simple extraction procedures, and the assay results were satisfactory.In chapter three, capillary electrophoresis coupled with amperometric detection (CE-AD) has been developed for the separation and determination of kaempferol, ferulic acid, vanillic acid, caffeic acid, gallic acid and protocatechuic acid in blueberry wine for the first time. The effects of working electrode potential, pH value and concentration of running buffer, separation voltage and injection time on CE-AD were investigated. Under the optimum conditions, the analytes could be separated in Na2B4O7-KH2PO4 buffer at pH 7.8 within 18 min. A 300μm diameter carbon disk electrode had good current responses at+0.95 V (versus SCE) for all analytes. The responses were linear with concentrations over three orders of magnitude with detection limits (S/N=3) at 10-8 g/mL magnitude for the analytes and the recoveries were in the range of 95.8%—106.7%. The method could be successfully applied to the analysis of real sample with satisfactory results and therefore recommended for use by the quality control departments of fruit wine producers.
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