Sensitive and selective liquid chromatography-electrospray ionization mass spectrometry analysis of ginkgolide B in dog plasma

As an important active constituent of Ginkgo biloba extract, ginkoglide B is a highly selective and competitive PAF receptor antagonist which has been widely used in clinical applications. A novel high-performance liquid chromatography-electrospray ionization mass spectromentry (LC-ESI-MS) method was developed for the determination of ginkgolide B in dog plasma. After liquid/liquid extraction with ether and high-performance liquid chromatography (HPLC) gradient separation with 0.01% of ammonia water (v/v) - methanol as the mobile phase, the deprotonized anions [M-H]^-1 at m/z 423 of ginkoglide B, and [M-H]^-1 at m/z 492 of internal standard (IS) glibenclamide were analyzed by LC-ESI-MS in selected ion monitoring (SIM) mode. Chromatographic separation was achieved in less than 9 min and calibration curve was linear over a concentration range of 0.1-20 ng/ml. The described assay method was successfully applied to the pre-clinical pharmacokinetic study of ginkoglide B. After intragastric administration of ginkgolide B to beagle dogs, C_max and T_max of ginkgolide B were 43.8 ± 6.24 ng/ml and 0.5 h, respectively, and the elimination half-life (t_1/2) was 2.85 ± 0.54 h.