Pharmacokinetic study of salvianolic acid A in rat after intravenous administration of Danshen injection

In order to research the pharmacokinetics of salvianolic acid A (SaIA), a herbal ingredient isolated from Salvia miltiorrhiza Bunge, after intravenous administration to rats, a specific and accurate high-performance liquid chromatography (HPLC) was developed. The assay procedure involved simple liquid-liquid extraction of SaIA and internal standard (IS, ethyl-p-hydroxybenzoate) from plasma into ethyl acetate. The organic layer was separated and evaporated under reduced pressure at 40 degrees C. The residue was reconstituted in the mobile phase and analyzed on an Inertsil C. column, monitored at 285 run. The mobile phase, which consisted of methanol-acetonitrile-water-formic acid (10:20:70:0.4, by vol), was used at a flow rate of 1.0 mL/rnin. The ratio of the peak area of the analyte to IS was applied to quantify the plasma samples. The standard curve for SaIA was linear (r(2) = 0.9999) in the concentration range of 0.75-150 mu g/mL. The limit of quantitation (LOQ) of SaIA was 0.75 mu g/mL. The intra- and inter-day precisions (RSD) of the quality control (QC) samples were in the ranges of 2.17-3.29 and 1.24-5.28%, respectively. Accuracy in the measurement of QC samples ranged from 94.7 to 101.1%. This method was validated for specificity. accuracy and precision and was successfully applied to the pharmacokinetic study of SaIA in rat plasma after intravenous administration of Danshen injection. Copyright (c) 2007 John Wiley & Sons. Ltd.