Preparation, characterization and in vitro and in vivo evaluation of a solid dispersion of Naringin.

Naringin (NA) is one of typical flavanone glycosides widely distributed in nature and possesses several biological activities including antioxidant, anti-inflammatory, and antiapoptotic. The aim of this study was to develop solid dispersion (SD) and to improve the dissolution rate and oral bioavailability of NA. NA-SD was prepared by the traditional preparation methods using PEG6000, F68, or PVP K30 as carrier at different drug to carrier ratios. According to the results of solubility and in vitro dissolution test, the NA-PEG6000 (1:3) SD was considered as an optimal formulation to characterize by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry and powder X-ray diffraction. Furthermore, oral bioavailabilities of NA-PEG6000 (1:3) SD and NA-suspension with the same dosage were investigated in SD rats. The results confirmed the formation of SD and the pharmacokinetic parameters of NA-PEG6000 (1:3) SD (C = 0.645 ± 0.262 µg/ml, AUC = 0.471 ± 0.084 µg/ml h) were higher than that of NA-suspension (C = 0.328 ± 0.183 µg/ml, AUC  = 0.361 ± 0.093 µg/ml h). Based on the results, the SD is considered as a promising approach to enhance the dissolution rate and oral bioavailability of NA.