| Although capillary electrophoresis(CE) has only a not long history of about twenty years, it has flourished in wide areas because of its inherent features such as extremely small sample volume, high separation speed and efficiency. Electrochemiacal dection(ED) is an important detection method which has good sensitivity and sometimes good selectivity for electroactive analytes . ED is compatible with small inner diameter of CE capillaries. CE-ED can combine the merits of these two methods and thus has good sensitivity and selectivity.Medicines are very important in our daily life. In order to use them properly, it's necessary to set up a system of medical determination. To meet this need, there has been a lot of work done in this field among which CE-ED has an eminent position for its advantages.In the preface of this paper, the history, the current situation and the trend of Capillary Electrophoresis have been firstly reviewed. Then, in the second section of the preface, the fundamental theory of CE and its characteristics, the technique of detection and of sample injection are descibed briefly. CE-ED technique is specially presented in the third section and the amprometric detection(AD) of the three main kinds of electrochemical detection methods is used in this paper and we introduce it concisely. Then, in the following part, the application of CE is summarized, which is focused on inorganic and organic small molecules, environment, food, biological analyses and medicine determinations and so on. After that, short comments are made on the long term potential of CE. The last part discusses the purpose and meaning of the work.Totally, this paper has been focused on applications of CE-ED in determination of medicines including traditional Chinese medicines and compound Chinesemedicines. All these are of great significance to broadening the applications of CE-AD to a certain extent. Now report as follow:1. Studies of active ingredients in cough syrup by capillary zone electrophoresis with amperometric detection. Ephedrine hydrochloride, promethazine hydrochloride and codeine phosphate are widely used in therapy as well as in abuse, it is important to select preferment analytical methods. This paper presents a simple, reliable and reproducible method, based on CE-AD for the determination of these three compounds. The selected optimal conditions are 1.00V(vs. Ag/AgCl., 3.0mol/L KC1) as working potential; 20mM PB(pH8.0) as the running buffer; 12kV as the separation voltage and 8s as the sampling time. The three analytes can be base-lined separated within 16min. Good linear relationships between the current responses and the concentrations of the analytes are obtained with the correlation coefficients better than 0.9993. The method is directly applied to the determination of the active ingredients in pharmaceutical preparations and the assay results are satisfactory.2.Separation and determination of psoralen and isopsoralen by capillary. zone electrophoresis with amperometric detection in traditional Chinese medicines A simple, reliable and reproducible method, based on capillary zone electrophoresis with amperometric detection, for separation and determination of psoralen and isopsoralen in several tradition Chinese medicines, such as malytea scurfpea fruit, divaricate saposhnikovia root, shou wu pian, gubenkechuan pian was described in this paper. A carbon-disc electrode was used as working electrode. The optimal conditions of separation and detection were pH7.6 phosphate buffer (0.02mol/l), 20kV for the separation voltage and 1.00V (vs. Ag/AgCl) for the detection potential. The linear ranges were from 1.0 10-7 to 1.0 10-5mol/l for psoralen, 3.0 10-7 to 5.0 10-5 mol/1 for isopsoralen with the correlation coefficient of 0.998, 0.998 and 0.992, respectively. The detection limits for psoralen and isopsoralen were 5.0 10-8, 2.0x10"7and 2.0 10-7 mol/1 (based on the signal to noise ratio of 3). The method built in this paper was directly applied to the determination of the traditional Chinese medicines without...
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