Simultaneous Quantification of Four Ginsenosides in Rat Plasma and Its Application to a Comparative Pharmacokinetic Study in Normal and Depression Rats Using UHPLC-MS/MS.

A sensitive method has been developed for simultaneous determination of ginsenoside Rh (G-Rh), ginsenoside Rb (G-Rb), ginsenoside Rc (G-Rc), and ginsenoside Rd (G-Rd) in rat plasma of normal and depression model group after oral administration of their solutions by using Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry (UHPLC-QQQ-MS). The biological samples were prepared by protein precipitation. Ginsenoside Rg (G-Rg) was used as an internal standard (IS). MS analysis was performed under the multiple reaction monitoring (MRM) with electron spray ionization (ESI) operated in the negative mode. The method showed good linearity over a wide concentration range (  > 0.999) and obtained lower limits of quantification (LLOQ) of 5 ng/mL. The whole analysis procedure could be completed in as short as 16.5 min. The intraday precisions, interday precisions, and stabilities were less than 10%. The extraction recoveries from rat plasma were exceeded 86.0%. The results indicated that there were significant differences between the two groups on pharmacokinetics parameters; the absorptions of four analytes in the depression group were higher than those in the normal group because the liver metabolism and internal environment of the model rats had been affected.