Established UPLC-MS/MS procedure for multicomponent quantitative analysis in rat plasma: A contrastive pharmacokinetics study of Qiangshen tablet in normal and kidney yang deficiency syndrome models.

Qiangshen tablet, an important prescription consisting of 14 kinds of Chinese herbal medicines, has been used for decades to treat kidney yang deficiency syndrome (KYDS) in China. Qiangshen tablet has been recorded in ChP (2015 edition) and possesses the effect of strengthening yang, invigorating qi and tonifying kidneys. In this research, a simple, reliable and specific method was established for simultaneous determination of stachydrine, psoralen, isopsoralen, morroniside, paeoniflorin and loganin in normal and KYDS rat plasma after intragastric administration of a Qiangshen tablet suspension by UPLC-MS/MS. Protein precipitation (PP) by acetonitrile and liquid-liquid extraction (LLE) by ethyl acetate - n-butanol (1: 1, v/v) were used for pretreatment of plasma samples. Chromatographic separation of two IS (Internal Standard) and six analytes was achieved using an ACQUITY UPLC® BEH C18 column (2.1 × 100 mm, 1.7 μm). The mobile phase consisted of 0.1% formic acid aqueous solution (solvent A) and acetonitrile (solvent B) with a gradient scheme. Multiple reaction monitoring (MRM) mode with positive and negative ion source switching was applied to perform the mass spectrometric analyses. This method has been validated with good linearity (r ≥ 0.9942) and acceptable precision and accuracy (RSD ≤ 11%, RE from -4.8% to 7.7%). The mean recovery values of the analytes and IS were all ≥68.28%, and the matrix effects ranged from 94.4% to 101.7%. The stability of the IS and analytes was measured throughout the experiment. The results showed significant differences between the pharmacokinetic traits of the analytes in the normal and KYDS groups, suggesting that pharmacokinetic procedures involving these analytes could be modified in cases of KYDS.