Study On Micellar Electrokinetic Capillary Chromatography For The Analysis Of Chinese Traditional Medicine Using Lauroyl Malic Acid Ester

Micellar electrokinetic chromatography (MEKC), actually employs the combined effects of partitioning and electrophoretic mobility of the compounds, has become one of the most important modes of capillary electrophoresis since it is suitable for the separation of neutral as well as charged molecules. It has proven to be a valuable tool for the analysis of Chinese traditional medicine. In this thesis, the application of MEKC in analysis of Chinese traditional medicine was reviewed. The following aspects were investigated by using lauroyl malic acid ester (LMAE) as surfactant in the new methods.1. The MEKC properties of lauroyl malic acid ester, auroyl citric acid ester, lauroyl sulfosalicylic acid ester and lauroyl acyl glutamic acid were investigated. And then the MEKC properties of4fatty acyl malic acid ester surfactants with difference carbon chains were tested, discussed the influce of carbon chain. The result shows that the lauroyl malic acid ester is best surfactant for MEKC. A MEKC method, using the lauroyl malic acid ester as surfactant, was established for simultaneous determination of ephedrine, pseudoephedrine, morphine, codeine phosphate, amygdalin, glycyrrhizin, apigenin and glycyrrhetinic acid in Kechuanning tablets. Under the optimum conditions of20mmol·L-1LMAE-20mmol·L-1Tris (containing13%2-propanol and9%acetonitrile, pH=8.0) as the running buffer, the baseline separation of eight components were obtained completely within18min. The detection limit for ephedrine, pseudoephedrine, morphine, codeine phosphate, amygdalin, glycyrrhizin, apigenin and glycyrrhetinic acid were0.8,0.8,0.3,0.3,0.6,0.4,0.3and1.0mg·L-1, respectively. The average recoveries of eight effective components were between95.7%～106%. The method is sensitive, rapid and can be used for the quality control of Kechuanning tablets.2. Two new methods based on MEKC-UV and MEKC-ESI-MS were established for simultaneous determination of coptisine, berberine, jatrorrhizine, phellodendrine and ligustrazine in Niuhuang Shangqing tablets. In the MEKC-UV method, five alkaloid components were obtained baseline separation within5min. It is suitable for rapid determination of quality control samples. In the MEKC-ESI-MS method, five alkaloid components were obtained baseline separation within18min. The detection limit for coptisine, berberine, jatrorrhizine, phellodendrine and ligustrazine were0.2,0.09,0.12,0.6and0.9mg·L-1. The average recoveries of five effective components were between96.0%～105%. It is suitable for the analysis of unknown complex samples since the qualitative ability of MS.3. A method of the separation and detection of ephedrine, pseudoephedrine, forsythin, amygdalin, chlorogenic acid, luteolin and caffeic acid in Chinese traditional medicine by microemulsion electrokinetic chromatography (MEEKC). The influence of microemulsion composition and pH on the separation were investigated. Under the optimum conditions of12mmol·L-1LMAE-8mmol·L-1borax (containing8%2-propanol and1.5%hexane, pH=7.5) as the running buffer, the baseline separation of seven components were obtained within12min. The detection limit for ephedrine, pseudoephedrine, forsythin, amygdalin, chlorogenic acid, luteolin and caffeic acid were0.20,0.20,0.50,0.40,0.30,0.20and0.20mg·L-1, respectively. The average recoveries of seven effective components were between93.6%～106%. The method is simple, rapid and suitable for the determination of ephedrine, pseudoephedrine, forsythin, amygdalin, chlorogenic acid, luteolin and caffeic acid in Chinese traditional medicine.