ABSTRACT
A simple and sensitive capillary electrophoresis method with field-enhanced stacking concentration for the analysis of protocatechuic aldehyde, protocatechuic acid, danshensu, rosmarinic acid and salvianolic acid B in Salvia miltiorrhiza var. miltiorrhiza f. alba was developed. The separation was achieved with a fused-silica capillary (75 microm x 50.2 cm, effective length was 40 cm) and a running buffer 15 mmol x L(-1) borax (pH 10.0) containing 20% CH3 OH. The UV detection wavelength was 210 nm. The applied voltage was 28 kV, and the cartridge temperature was 25 degrees C. Water plug was introduced from the anode by 0.5 psi x 4 s before injection. Sample was injected by electrokinetic injection - 8 kV x 3 s. The linear range of protocatechuic aldehyde is 3.0-60.00 mg x L(-1) (R2 = 0.999 8); that of protocatechuic acid, danshensu, rosmarinic acid and salvianolic acid B are 1.0-20.00 mg x L(-1) (R2 are 0.999 1, 0.999 4, 0.998 9 and 0.999 8, respectively), and the limits of detection of five analyts are 0.55, 0.40, 0.25, 0.32, 0.38 microg x L(-1), respectively, Stacking factor is higher and precision is satisfactory. The recoveries ranges were from 97.3% to 99.8%. The proposed method was used to determine the protocatechuic aldehyde, protocatechuic acid, danshensu, rosmarinic acid and salvianolic acid B in S. miltiorrhiza var. miltiorrhiza f. alba. The proposed method is simple, rapid, accurate and high sensitivity, and can be used to control of the quality of S. miltiorrhiza var. miltiorrhiza f. alba.