Development Of Online-concentration Technique For Capillary Electrophoresis

This report mainly focuses on the enrichment mechanism of CE and CEC, as well as the application of monolithic materials in the selective enrichment and separation of traditional Chinese medicine, peptides and proteins.The electric property of CEC will lead to some special phenomenon in the separation procedure,which can not be explained by normal chromatography theory. Base on the relaxation theory, chromatographic zone compression effect in continuous stacking and special peak compression in ion-exchange of CEC was studied.Various monolithic columns of CEC with different selectivity were prepared. Poly (butyl methacrylate–co-ethylene dimethacrylate) column was used to separate the extracts of Shiyacha by stepwise gradient elution. With the combination of on-line concentration technique, the detection limit of flavonoids could be decreased to 25 ng for apigenin. Monolithic columns with weak electroosmotic flow (EOF) were prepared by binary porogenic solvents, on which the ionic component in Chinese medicine was enriched and analyzed with the developed on-line concentration technique. In addition, weak anion exchange and weak cation exchange monolithic columns were prepared and applied to the concentration and separation...