Separation and determination of chalcones from Carthamus tinctorius L. and its medicinal preparation by capillary zone electrophoresis

A new capillary zone electrophoresis (CZE) method was developed for simultaneous assay of four chalcones, hydroxysafflor yellow A, safflor yellow A, safflamin C, and safflamin A, in the Chinese herbal extract from Carthamus tinctorius L. The optimum buffer system was 30 mM borate buffer (Na2B4O7/HCl, pH 9.00) with 10% (v/v) methanol. The voltage was 15 kV and detection was at 270 nm. Regression equations revealed linear relationships (correlation coefficients: 0.9973, 0.9992, 0.9989, and 0.9996) between the peak area of each compound and its concentration. The within-day relative standard deviations of migration times and peak areas were < 1.53 and 4.14%, respectively. The effects of several CE parameters on the resolution were studied systematically. The contents of four chalcones in Carthamus tinctorius L. were successfully determined with satisfactory repeatability and recovery. The possibilities of using this method for the determination of chalcones in Chinese medicinal preparation was also tested.