HPLC同时测定大鼠血浆中的总黄芩素和总大黄酸的浓度及药动学研究

Objective: To establish a HPLC for simultaneous determination of total baicalein and rhein after enzymatic hydrolysis and applied to pharmacokinetics study. Methods: Quercetin as internal standard, plasma samples enzyme hydrolysis with β-glucuronidase and sulfatase, then liquid-liquid extraction sample. The processed rat plasma samples were separated on a Welchrom-C18 column. The mobile phase was acetonitrile-water (0.2% phosphoric acid, 0.1% triethylamine, v/v) for gradient elution，detection wavelength was 270 nm. Results: Chromatograms showed endogenous peaks not interfering with the analysis. The calibration curves of baicalein and rhein were both in good linearity within the range of 0.027 ~ 28.080 and 0.043 ~ 10.400 μg/mL, respectively. The mean extraction recoveries were more than 75% while the precisions were less than 8% . The results of stability experiment meet certain requirements for the biopharmaceutical analysis. Conclusion: The method has high sensitivity, precision, and can be applied to determine rhein and baicalin in plasma after hydrolysis. This method also can be used for pharmacokinetics study of baicalin and rhein.