ABSTRACT
ObjectiveTo clarify the scientific validity of in vivo pharmacokinetic determination of the whole drug composition in Shenbai nanosuspension in rats， and to provide methodological guidance and theoretical basis for the in vivo study of multi-component complex system of traditional Chinese medicine（TCM） preparations. MethodThe concentration of the overall components， mainly total saponins and total polysaccharides in Shenbai decoction and Shenbai nanosuspension， was determined in rat plasma at different times by area under the absorbance-wavelength curve method（AUAWC）， and the concentration of individual ginsenoside Rg1 was determined by high performance liquid chromatography（HPLC）， and the methodology was verified. The pharmacokinetic parameters of the whole component were compared with those of ginsenoside Rg1 to evaluate the in vivo operational characteristics of the two preparations. ResultThe methodological investigations of AUAWC and HPLC were in accordance with the requirements. AUAWC analysis showed that the overall components in both the decoction group and the nanosuspension group showed a one-compartment model， with half-life（t1/2） of 2.43 h and 2.04 h， respectively. The relative bioavailability of Shenbai nanosuspension was 138.99%. HPLC assay showed that ginsenoside Rg1 in the decoction group and the nanosuspension group showed a two-compartment model， with distribution half-life（t1/2α） of 0.13 h and 2.55 h， and elimination half-life（t1/2β） were 14.28 h and 3.85 h， respectively. The relative bioavailability of Shenbai nanosuspension was 127.49%. Compared with Shenbai decoction， the time to peak（tmax）， peak concentration（Cmax） and area under the drug-time curve（AUC） of the overall components and ginsenoside Rg1 in Shenbai nanosuspension were increased. ConclusionThe established AUAWC can be used for the pharmacokinetic study of the overall components of TCM preparations， which is complementary to the results of individual components measured by HPLC， and can provide useful reference for the in vivo study of new dosage forms of TCM.
