Simultaneous determination of seven ginsenosides in rat plasma by high-performance liquid chromatography coupled to time-of-flight mass spectrometry: application to pharmacokinetics of Shenfu injection.

A high-performance liquid chromatography coupled to time-of-flight mass spectrometry (HPLC-TOF MS) method was successfully developed and validated for the identification and determination of seven ginsenosides, Re , Rf , Rb1 , Rc , Rb2 , Ro and Rd , in a Chinese herbal preparation, Shenfu injection, and rat plasma. Based on the method, the pharmacokinetic profiles of the seven ginsenosides were investigated following intravenous administration of single dose of Shenfu injection to six rats. The established method had high linearity, selectivity, sensitivity, accuracy and precision. The pharmacokinetic results showed that Rb1 , Rc and Rb2 had similar pharmacokinetic profiles and relatively long half-life values (19.29 ± 6.36, 29.54 ± 22.91 and 35.60 ± 30.66 h). The half-lives of Rf and Rd were 4.21 ± 3.68 and 8.49 ± 5.20 h, respectively, indicating that they could be metabolized more rapidly than Rb1 , Rc and Rb2 .