Abstract
Background: Guizhi Decoction (GZD), a traditional Chinese medical formula, has been commonly used to treat fever, sweating, and cold in China. Methods: The high performance liquid chromatography -tandem mass spectrometry ( HPLC-MS/MS ) method was established for the determination of 10 compounds, including cinnamic acid , paeoniflorin, albiflorin, liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, glycyrrhizic acid, glycyrrhetinic acid, and 6-gingerol. And the specificity, linearity, lower limit of quantification (LLOQ), lower limit of detection (LLOD), precision and accuracy, recovery, matrix effect, and stability were used to verify the HPLC-MS/MS method. This validated method was successfully applied for pharmacokinetic study of the 10 compounds in rat plasma after oral administration of GZD in three doses (40 g crude drug·kg −1 , 20 g crude drug·kg −1 , 10 g crude drug·kg −1 ) and intravenous injection of GZD extraction at a dose of 2.0 g crude drug·kg −1 .The measurements of pharmacokinetic parameters including AUC 0–∞ , T 1/2 , T max , C max , Vz_F, Cl_F, and MRT, were performed using a non-compartmental model with Winnonlin 8.1 software. Results: The results showed that 10 compounds were detected in plasma after oral administration of GZD. the compounds (except for glycyrrhetinic acid) reached the maximum blood concentration quickly, whose Tmax was about 0.1-0.2 min. And a total of 9 compounds were detected after intravenous injection of GZD. The plasma concentration-time curve of these compounds declines rapidly at the beginning, and then decreased slowly, indicating that the plasma concentration-time curves were double exponential function curves. Conclusions: In this study, the developed method was suitable for pharmacokinetic analysis of the main compounds of GZD in rat plasma, and may reveal the pharmacodynamic material basis of GZD and provide a reference for the rational use of GZD in the clinic.
The Determination of 10 Compounds of GuiZhi Decoction in Rat Plasma after Oral Administration by HPLC-MS/MS and its Application to a Pharmacokinetic Study
