Determination of Protocatechuic Aldehyde, Danshensu, Salvianolic Acid B and Gallic Acid in Chinese Medicine 'SHUANGDAN' Granule by MEKC

A simple, accurate and effective micellar electrokinetic capillary chromatography (MEKC) method for the separation and determination of protocatechuic aldehyde (PA), danshensu (DSS), salvianolic acid B (SAB) and gallic acid (GA) in Chinese medicine 'SHUANGDAN' granule was developed in this work. The separation was carried out in a 50.0 cm (42.0 cm to the detector) × 75 µm i.d. fused-silica capillary using the optimum buffer solution containing 5.0 mM borate, 15 mM phosphate, 35 mM SDS and 10% (v/v) acetonitrile. The linear relationships between the concentration of the analytes and the corresponding peak areas were investigated, and excellent linear behavior over the investigated concentration ranges was revealed (R²: 0.9985 for PA, 0.9994 for DSS, 0.9989 for SAB and 0.9991 for GA, respectively). The proposed method was successfully applied to the determination of these four active components contained in 'SHUANGDAN' granule. The recoveries of these four components were 97.6–101.2%, 97.6–100.5%, 96.9–101.6% and 97.6–102.9%, respectively.