LC–MS determination and pharmacokinetic study of six phenolic components in rat plasma after taking traditional Chinese medicinal-preparation: Guanxinning lyophilized powder for injection

A traditional Chinese medicinal preparation (TCMP) named Guanxinning lyophilized powder for injection composed of Salvia miltiorrhiza Bge. (SMB) and Ligusticum chuanxiong Hort. (LCH) was studied. In order to learn the kinetic behaviors of the lyophilized powder and provide proofs for rational administration, we have developed a sensitive and reproducible method for determination and pharmacokinetic study of six main phenolic components {danshensu (DSS), protocatechuic acid (PAC), protocatechuic aldehyde (PAL), chlorogenic acid (CHA), caffeic acid (CAA) and salvianolic acid B (SAB)} of Guanxinning in rat plasma using liquid chromatography–mass spectrometric (LC–MS) method. Sample preparations were carried out by protein precipitation with the addition of methanol followed by liquid–liquid extraction with ethyl acetate–ethyl ether (3:1, v/v) after internal standard (IS, galic acid) spiked. After evaporation to dryness, the resultant residue was reconstituted in methanol and injected onto a Kromasil C18 column (150 mm × 4.6 mm i.d. with 5 μm particle size). The analytes were analyzed by using negative electrospray ionization (ESI) mass spectrometry in selected ion monitoring (SIM) mode. The method was with good linearity in the range 0.342–85.0 μg mL−1 for DSS, 0.0647–12.9 μg mL−1 for PAC, 0.0933–18.7 μg mL−1 for PAL, 0.0085–3.40 μg mL−1 for CHA, 0.0138–2.75 μg mL−1 for CAA and 0.0272–810 μg mL−1 for SAB (r > 0.99). The average extract recoveries of the six analytes from rat plasma were all no less than 75%, the precision and accuracy determined were all within the required limits. This LC–MS method was successfully applied to pharmacokinetic study of the six phenolic components of Guanxinning lyophilized powder for injection in rats.