Study On Bioanalytical Methods For The Pharmacokinetics Of Ginsenoside Compound K

Background : Ginsenoside compound K( GCK) is the main metabolite of the protopanaxadiol type of Panax ginseng C.A. Meyer, GCK could significantly inhibit the proliferation of cancer cells, block the cell division G1 phase and induce its apoptosis. but there is no report about human pharmacokinetic study in positive mode after oral administration of GCK.Objective: A selective and highly sensitive LC-MS/MS method was developed for determination of GCK in human plasmawith metal adduct ion of lithium. And the method should be applied in a pharmacokinetic study of GCK in healthy Chinese volunteers. Also an LC-MS/MS method was to be developed for determination of GCK and its metabolites in human feces. The method should be applied in a single drug tolerance and material balance pharmacokinetic study in healthy Chinese volunteers.Method:GCK and paclitaxel(internal standard) were extracted from 50 μL of human plasma using methyl tert-butyl ether. Chromatographic separation was performed in a Phenomenex Gemini C18 column(50 mm × 2.0 mm; 5 μm) with a mobile phase consisting of acetonitrile-water and 0.2 m M lithium carbonate at a flow rate of 0.5 m L/min in gradient elution. Mass spectrometric detection was performed in a positive reaction monitoring mode using m/z 629 â†' 449 transition for GCK and m/z 860 â†' 292 transition for paclitaxel. After extraction from human feces by protein precipitation with acetonitrile. GCK, its metabolites and simvastatin(IS) were separated on a Agilent Phenyl-Hexyl column(50 mm× 2.1 mm; 1.8 μm) with a mobile phase consisting of acetonitrile-water and 0.2 % formic acid at a flow rate of 0.7 m L/min in gradient elution. Mass spectrometric detection was performed in a positive reaction monitoring mode using m/z 425.3 â†' 217.2 transition for GCK and PPD, m/z 477.1â†' 143.0 transition for 477-1 and 477-2,m/z 436.2â†' 285.2 transition for simvastatin.Results : The GCK calibration curve was linear over the concentration range of 1.00–1000 ng/m L(r2 > 0.9988). The intra- and inter-day precision values were within 8.4% and the accuracy ranged from ?4.8% to 6.5%,which were within the acceptable limits across all concentrations. This method was successfully applied to a pharmacokinetic study of GCK tablets in 12 healthy Chinese volunteers. After single and multiple oral administation of GCK,mean peak plasma levels(Cmax) of 652 ± 180 ng/ml and Tmax of 2.63 ±1.17 h and t1/2 of 5.97 ± 0.68 h were obtained;AUC(0-t) were calculated to be 3654 ± 853 h·ng·m L?1 and AUC(0-∞) were calculated to be 3814 ± 893 h·ng·m L?1. A methed was developed to determination of GCK and its metabolites in human feces. The calibration curve of GCK and PPD were linear over the concentration range of 0.50–100 μg/g and The calibration curve of 477-1 and 477-2 were linear over the concentration range of 0.05–5.00 μg/g. The method was successfully applied to a pharmacokinetic study of GCK tablets(100mg and 600 mg in 22 healthy Chinese volunteers.Conclusion:This study developed fast,selective, and sensitive LC?MS/MS with metal adduct ion of lithium for the determination of GCK in human plasma and LC?MS/MS methods for the determination of GCK and its metabolites in human feces, respectively. Two validated method were successfully applied to the pharmacokinetic study of GCK tablets in volunteers.