Analysis And Determination Of Chinses Herb By Capillary Electrophoresis

This thesis consists of five chapters. Chapter one: Introduction of the basic theory?of capillary eleetrophoresis, the optimum performance of CE and the application of CE on the analysis of Chinese herb. Chapter two: A relation between the eiiecti\ C mohilit\ at different pH values and the buffer pH value which was derived from the basic electrophoresis theory and the dissociation equilibrium of a binary acid. eased on this relation, the dissociation constants (pKa1 pKa2) of the interested compounds (five anthraquinones) were determined. In addition, when organic modifiers were added to the buffer system, the changes of pKa values of the five compounds were also investigated. Chapter three: A CE method to separate and determine the five active components, gastrodin, vanillyl alcohol, p-hydoxvhenzyl alcohol, \inllln and p-hydroxybenzyl aldehyde in Chinese herb Gastrvdiri Juiti Bl. and its preparations was developed. Baseline separation was achieved under the optimum experiment buffer condition of 24mmol/l borate ?8% ethanol (plI9 56) and the active components were quantitatively analyzed within 15mm. In addition. the effects of organic modifier and electrolyte concentration on the separation were a o invest uated. Chapter four: a MEKC method to analyze the active components of psoralen and isopsoralen in Chinese herb psoraleci con/i/o/ia L. was developed. It was found that the optimum separation condition for the analysis ol these compounds was a buffer solution which contained phosphate. borate and sodium dodecyl sulfate (pH=9.2). Through optimization of the experimental condition. the two isomers could be baseline separated and their contents in the methanol extracted sample were quantitatively analyzed. The linear con Jut ion equations are v0.56 I + 1 7.2x, r~0.998 for isopsoralen and yO.28S-rl 5.4 x. rO.995 for psoralen respectively. Chapter five: A method for the separation of anthraquinone compounds based on nonaqueous capillary electrophoresi s has been developed. The electrophoretic condition was 30 mmol/L tetrabutvlammoniuni bromide in acetonitrile. Using the nonaqueous medium, three anthraquinone compounds can be separated within 6 minutes. The reproducibility of retention time for each component was below 0.35% and the reproducibility of peak height was helo\\ .i8...