A high performance liquid chromatography method was established for simultaneously determining four bioactive components, salicin, liquiritin, paeonolum, and imperatorin in Fengshiding capsule, a widely used traditional Chinese medicine for treating rheumatic disease. The chromatographic separation was performed on a Shimadzu Shim-pack Stable Bond C18 column using gradient elution with methanol and water. The analytical method was validated through precision, repeatability and stability, and the relative standard deviation values were less than 3%, respectively. The recoveries of the four investigated compounds ranged from 95.80 to 101.21% with relative standard deviation values less than 3.2%. Then this proposed method was successfully applied to determine six batches of Fengshiding commercial products of capsule dosage form from two pharmaceutical factories. This study might provide a basis for quality control for this traditional Chinese medicine preparation.
Keywords: Fengshiding capsule; high performance liquid chromatography; imperatorin; liquiritin; paeonol; salicin.