Preparation and In Vivo-In Vitro Evaluation of Polydatin-Phospholipid Complex with Improved Dissolution and Bioavailability

In spite of various biological activities. Polydatin showed severely limited use in the clinic applications because of its poor oral bioavailability. As a promising formulation approach, the development of polydatin phospholipid complex (PPC) was used to improve the solubility, and oral bioavailability. In this study, solvent evaporation method was employed to obtain the PPC. The formation mechanism of PPC was discussed based on the information from fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and X-ray power diffraction (XRD) tests. Besides, the in vitro dissolution and in vivo pharmacokinetic properties of PPC were also studied. The water solubility of polydatin in the complex was increased compared with pure polydatin. FT-IR spectra indicated the existence of some molecular interaction between the phospholipid molecule and polydatin. DSC and XRD results showed that PPC obtained was in the form of amorphous structure. In vitro dissolution research showed that the cumulative dissolution of PPC was 80.36% after 8 h, which was improved as compared to 63.84% of polydatin during the same period. The pharmacokinetic study showed that the AUC0-∞ of PPC and polydatin in rats were 748.2 and 340.6 μg•min/mL, which markedly indicated that phospholipid complex could contribute to a 2.2-fold increase in oral bioavailability of polydatin. In vivo-in vitro evaluation results showed that PPC was a promising approach to improve the water solubility and oral bioavailability of polydatin.