Pharmacokinetics and bioavailabilities of geniposide in Beagle dogs after oral administration Xingnaojing

OBJECTIVE: To establish a method for determination of geniposide in Beagle dogs plasma by high performance liquid chromatography (HPLC), and study the pharmacokinetics and bioavailability of geniposide in Beagle dogs after oral administration Xingnaojing. METHOD: To determine the geniposide in Beagle dogs plasma by HPLC after oral administration or intravenous injection Xingnaojing, and the pharmacokinetic parameters were calculated by the software of Kinetica. RESULT: The good linearity range of geniposide was 1.24 - 158.88 mg x L(-1). The main pharmacokinetic parameters after oral administration was as follows: Cmax (11.8 +/- 0.6) mg x L(-1), Tmax (52.0 +/- 4.5) min, AUC(1280.8 +/- 172.0) mg x min x L(-1), MRT(118.7 +/- 25.4) min, and these parameters after intravenous injection was follows: Cmax 107.4 +/- 6.3) mg x L(-1), AUC(7930.1 +/- 670.0) mg x min x L(-1), MRT(92.4 +/- 5.1) min. The bioavailability of geniposide in Beagle dogs after oral administration Xingnaojing was (6.46 +/- 0.87)%. CONCLUSION: The HPLC method had good applicability. The extract recovery, method recovery, intra-day precision and inter-day precision of the method were all met the requirements. The stability in conditions of room temperature and freeze-thaw cycle was good. The results indicated that the oral administration bioavailability of geniposide was in low degree.