Simultaneous determination of tanshinol, protocatechuic aldehyde, protocatechuic acid, notoginsenoside R1, ginsenoside Rg1 and Rb1 in rat plasma by LC–MS/MS and its application

Dantonic pill, consisting of Salviae miltiorrhize, Panax notoginseng and Borneol, is a widely used compound Chinese medicine for preventing and treating ischemic cardiovascular diseases in China. In the present study, an original and sensitive method for simultaneous determination of tanshinol (i.e. danshensu), protocatechuic aldehyde, protocatechuic acid, notoginsenoside R1, ginsenoside Rg1 and Rb1 in rat plasma by liquid chromatography–tandem mass spectrometry operated in positive/negative ion switching mode was established and validated. The lower limits of quantification for tanshinol, protocatechuic aldehyde, protocatechuic acid, notoginsenoside R1, ginsenoside Rg1 and Rb1 were 5, 0.5, 1, 0.5, 0.5 and 2 ng/mL, respectively. All of the calibration curves showed good linearity over the investigated concentration range (r > 0.99). Validation results demonstrated that the above compounds were accurately, precisely and robustly quantified in rat plasma. The method was successfully applied to characterize the pharmacokinetic profiles of all six compounds in rats following a single oral administration of Dantonic pill.