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

A SPE-HPLC-MS method for simultaneous quantification of plasma concentrations of five constituents of YPFS was developed and validated. Cycloastragenol and cimifugin, the metabolites of astragaloside IV and prim-O-glucosylcimifugin in vivo, have demonstrated good pharmacokinetic behavior among the detected constituents in this study.187