Abstract
A simple and sensitive high-performance liquid chromatographic method was developed for the simultaneous determination and pharmacokinetic analysis of seven alkaloids dehydroevodiamine (DHED), 10-hydroxyrutaecarpine (HDR), evodiamine (EDM), rutaecarpine (RCP), 1-methyl-2-n-nonyl-4(1H)quinolone (MNQ), evocarpine (ECP), and dihydroevocarpine (DHE), and two flavonoids isorhamnetin-7-O-rutinoside (RIM) and diosmetin-7-O-β-d-glucopyranoside (GRD) in rat plasma after oral administration of Wuzhuyu decoction. The flow rate was kept at 1.0 ml/min and the detection wavelength was set at 300 nm. The calibration curves were linear in the range of 0.5013–30.076 μg/ml for DHED, 0.2161–21.608 μg/ml for RIM, 0.161–12.876 μg/ml for HDR, 0.2146–21.457 μg/ml for GRD, 2.0464–40.928 μg/ml for EDM, 1.0398–31.194 μg/ml for RCP, 0.5970–35.818 μg/ml for MNQ, 0.8371–20.928 μg/ml for ECP, and 0.5167–31.003 μg/ml for DHE. The precision (relative standard deviation (RSD), %) for all was less than 10% and the accuracy (relative error (RE), %) was within ± 10%. The results demonstrated that the assay had remarkable reproducibility with acceptable accuracy and precision. The lower limit of quantifications for the compounds in plasma ranged from 0.12 to 0.23 μg/ml and the lower limit of detections ranged from 0.024 to 0.076 μg/ml. This validated method has been successfully applied in the pharmacokinetics study of seven alkaloids and two flavonoids after orally administrating the Wuzhuyu decoction to rats.
Acknowledgements
The authors thank the NIH Fellows Editorial Board (NIH, Bethesda) for editorial assistance. This project was supported in part by the National Sciences and Technology Program (2006BAI08B03–09; 2006BAI06A01–02) of China, National High Technology Research and Development Program of China (2002AA2Z343C; 2004AA2Z3783), Beijing Municipal Special-Purpose Science Foundation of China (Z0004105040311).
Notes
1. Present address: Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.