Comparative analysis of absorbed ingredients and metabolites, and pharmacokinetic studies of Zhimu-Huangbai herb pair in the plasma of normal and type 2 diabetes mellitus rats by UHPLC-linear trap quadrupole-orbitrap MS and LC-MS/MS.

A new rapid ultra-high-performance liquid chromatography coupled with linear trap quadrupole orbitrap mass spectrometry method was established for the qualitative analysis of absorbed ingredients and metabolites of Zhimu-Huangbai herb pair, which is used to treat type 2 diabetes mellitus. A total of 16 absorbed ingredients and 11 metabolites were identified in normal and type 2 diabetes mellitus rats, respectively. Such findings indicated that the diabetic model had no effect on the type of components in plasma. Seven absorbed ingredients and 11 metabolites were first identified after the oral administration of Zhimu-Huangbai herb pair. Thereafter, ultra-high-performance liquid chromatography coupled with linear trap quadrupole orbitrap mass spectrometry and liquid chromatography-API4000 triple quadrupole mass spectrometer methods were established and validated for pharmacokinetic comparative studies of seven major bioactive components in normal and type 2 diabetes mellitus rats. Partial pharmacokinetic parameters in the plasma of type 2 diabetes mellitus rats were significantly different from those in normal rats. To our knowledge, this is the first comparison of absorbed ingredients and metabolites of Zhimu-Huangbai herb pair, and its use in pharmacokinetic studies between normal and type 2 diabetes mellitus rats. Ultimately, our findings provide insights into the clinical usage of Zhimu-Huangbai herb pair.