CZE Determination of Flavonoids in Halenia elliptica

A capillary zone electrophoretic method with UV detection at 254 nm has been developed and validated for quantitative analysis of three flavonoids, luteolin?7?O?β?D-glycoside, genkwanin, and luteolin, in Halenia elliptica. The applied voltage was 15 kV and the capillary temperature was kept constant at 25 °C. The effects on migration of buffer pH, electrolyte concentration, and organic modifier were studied systematically. Optimum separation was achieved with 20 mM borate buffer at pH 9.00 containing10% (v/v) acetonitrile. Regression equations revealed a good linear relationship between the peak area of each compound and its concentration. All correlation coefficients were 0.9999. The relative standard deviations of migration time and peak areas were, respectively, <1.58 and 5.02%(intra-day) and <1.69% and 5.36% (inter-day). The amounts of the three compounds in the different parts of H. elliptica (stems, leaves, and flowers) and in the extracts of the flowers obtained with different solvents (100% methanol and 50% and 75% methanol in water) were successfully determined with satisfactory repeatability and recovery.