Pharmacokinetic Study of the Baicalin from Ultramicro-pulverised Powder of Huanglian jiedusan(HLJDS) in Rabbits

High performance liquid chromatography(HPLC) was applied to determine the concentrations of plamsa baicalin in two groups of rabbits after administering the ultramicro-pulverised powder and the ordinary powder of HLJDS(in water suspension) by gastrogavage respectively.The plasma concentration-time data of baicalin were dealt with Pharmaceutical Kinetics Software(PKS).Pharmacokinetics characteristics of both the ultramicro-pulverised powder and ordinary powder of HLJDS were compared.The results showed that the best pharmacokinetic model of baicalin in either group was two-compartment open model.The main pharmacokinetic parameters of baicalin of ultramicro-pulverised powder were as follows: Ka=0.497 h-1,t1/2α=2.556 h,t1/2β=8.46 h,AUC0→∞=3.401 μg·h/mL,Vd=6.752 L/kg,Tpeak=3.005 h,Cmax=0.311 μg/mL;The main pharmacokinetic parameters of baicalin of the ordinary powder were as follows:Ka=0.419 h-1,t1/2α=2.74 h,t1/2β=5.83 h,AUC0→∞=2.611 μg·h/mL,Vd =12.890 L/kg,Tpeak=3.645 h,Cmax=0.215 μg/mL.As compared to the baicalin from ordinary powder,the relative bioavailability of baicalin from ultramicro-pulverised powder was increased by 30.26%.These data presented above indicated that the bioavailbility of baicalin from HLJDS could be greatly improved after processing and preparing by the technique of ultromicro-pulverization.