A sensitive method for determination of salvianolic acid A in rat plasma using liquid chromatography/tandem mass spectrometry

Salvianolic acid A (SAA), a major effective constituent of Salvia miltiorrhizas , is widely used in traditional Chinese medicine. A sensitive rapid analytical method was established and validated for SAA in rat plasma, which was further applied to assess the pharmacokinetics of SAA in rats receiving a single oral dose of SAA. The method used liquid chromatography tandem mass spectrometry in multiple reaction monitoring mode with chloramphenicol as the internal standard. A simple liquid–liquid extraction based on ethyl acetate was employed. The combination of a simple sample cleanup and short chromatographic run time (3 min) increased the throughput of the method substantially. The method was validated over the range 1.4–1000 ng/mL with a correlation coefficient >0.99. The lower limit of quantification was 1.4 ng/mL for SAA in plasma. Intra‐ and inter‐day accuracies for SAA were 95–113 and 98–107%, and the inter‐day precision was less than 12%. This method is more sensitive and faster than previous methods. After a single oral dose of 100 mg/kg of SAA, the mean peak plasma concentration ( C max ) of SAA was 318 ng/mL at 0.5 h, the area under the plasma concentration–time curve (AUC 0–12 h ) was 698 ± 129 ng·h/mL, and the elimination half‐life ( T 1/2 ) was 3.29 h. Copyright © 2008 John Wiley & Sons, Ltd.