A sensitive liquid chromatographic-mass spectrometric method for simultaneous quantification of six iridoid glycosides from Zhi-zi-chi Decoction in rat plasma and its application to a pharmacokinetic study

► An LC-MS method was developed for the pharmacokinetic study of Zhi-zi-chi Decoction. ► Good sensitivity, recovery and reproducibility were obtained using the method. ► The validated method was successfully applied to a comparative pharmacokinetic study.