ABSTRACT
Objective:To prepare daidzein nanosuspension capsules,and to investigate intestinal absorption and oral bioavailability by comparing with commercial daidzein capsules. Method:Daidzein nanosuspensions were prepared by precipitation method combined with high pressure homogenization,orthogonal design method was utilized to optimize its formulation.Daidzein nanosuspensions was characterized by X-ray powder diffraction(XRPD),Fourier transform infrared spectroscopy(FT-IR),transmission electron microscope(TEM),and indexes including mean particle size,polydispersity index(PDI),and Zeta potential.Intestinal absorption study was carried out to compare the accumulative permeated amount of daidzein from daidzein nanosuspensions and commercial daidzein capsules.Biodistribution of daidzein in gastrointestinal tract was investigated,and oral bioavailability was examined through pharmacokinetic study by HPLC. Result:The in vitro small intestinal absorption enhancement ratio of daidzein nanosuspension capsules was approximately 2.49-fold higher than that of commercial capsules(PConclusion:Daidzein nanosuspensions prepared by combined method can be applied to the production of capsules,which is beneficial to increase the absorption of drug in small intestine and improve its bioavailability after oral administration.