Simultaneous determination of danshensu, ferulic acid, cryptotanshinone and tanshinone IIA in rabbit plasma by HPLC and their pharmacokinetic application in danxiongfang

A selective and sensitive reversed-phase high performance liquid chromatography method was developed and validated for the simultaneous determination of danshensu, ferulic acid, cryptotanshinone, and tanshinone IIA in rabbit plasma using p-hydroxybenzoic acid as internal standard. Liquid–liquid extraction was used for sample preparation. Chromatographic separation was successfully achieved on an Agilent HC-C₁₈ column using a mobile phase composed of methanol–water (from 20:80 to 80:20, v/v) containing 0.5% (v/v) glacial acetic acid. The mobile phase was employing gradient elution at a flow rate of 1.0 ml/min. The method showed good linearity and no endogenous material interfered with the marked compounds and I.S. peaks. The limit of quantification of danshensu, ferulic acid, cryptotanshinone, and tanshinone IIA were 0.1, 0.03, 0.05, and 0.05 μg/ml, respectively. The average extract recoveries of the four compounds from rabbit plasma were all over 60%. The precisions determined from 5 days were all within 10%. The established method has been successfully applied in the pharmacokinetic study and drug interaction of danshensu, ferulic acid, cryptotanshinone, and tanshinone IIA in rabbits after intravenous administration of danxiongfang, a useful compound preparation of traditional Chinese medicine.