Development of an SPE-HPLC-MS method for simultaneous determination and pharmacokinetic study of bioactive constituents of Yu Ping Feng San in rat plasma after oral administration.

ETHNOPHARMACOLOGICAL RELEVANCE: Yu Ping Feng San (YPFS, in Chinese: Jade Windscreen Powder), a well-known traditional Chinese medicine, is commonly used to cure the diseases of respiratory systems and immune systems. AIM OF THE STUDY: A selective and sensitive high-performance liquid chromatography coupled with mass spectrometry method (HPLC-MS) was developed and validated for simultaneous quantification of cycloastragenol, formononetin, calycosin, 4'-O-β-glucopyranosyl-5-O-methylvisamminol (GMV) and cimifugin in rat plasma after oral administration of Yu Ping Feng San decoction. MATERIALS AND METHODS: Plasma samples were extracted via solid-phase extraction (SPE), separated on a Zorbax SB-C18 column, detected by single quadruple mass spectrometry with an electrospray ionization interface, and quantified using selected ion monitoring mode. The current SPE-HPLC-MS assay was validated for linearity, intra-day and inter-day precisions, accuracy, extraction recovery and stability. The method was applied to a comparative pharmacokinetic study after administration of Yu Ping Feng San to rats at different doses (10, 20 and 40g/kg). RESULTS: The calibration curves were linear over the ranges 0.50-50ng/mL and 17.36-1736ng/mL. Intra- and inter-day precisions (relative standard deviations) were from 0.45% to 10.95%, and accuracy (relative recovery) from 95% to 115%. The extraction recoveries were greater than 88.42% for all analytes. Dose-dependence was shown for some constituents in the drug concentration-time profiles. Among all the active ingredients detected, cimifugin had the highest blood concentration (881-1510ng/mL), and cycloastragenol had the longest retention time in the rat body (15.06-20.44h). CONCLUSION: This analytical method is a selective, sensitive, precise, accurate, and reliable assay for simultaneous determination of cycloastragenol, calycosin, formononetin, GMV, and cimifugin in rat plasma.