Preparation and characterization of resveratrol/hydroxypropyl-β- cyclodextrin inclusion complex using supercritical antisolvent technology

Abstract

The inclusion complex of resveratrol (RV) and hydroxypropyl-β- cyclodextrin (HP-β-CD) prepared by supercritical antisolvent (SAS) process was investigated to improve its aqueous solubility. The phase solubility diagram with HP-β-CD was classified as A L type, and the calculated apparent complexation constant (K C) was 5,988 M -1 at 298K. Inclusion complexes were analyzed by differential scanning calorimetry (DSC), powder X-ray diffractometry (PXRD), Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). No endothermic and characteristic diffraction peaks corresponding to RV were observed for the inclusion complex in DSC and PXRD. FT-IR study demonstrated the presence of intermolecular hydrogen bonds between RV and HP-β-CD in inclusion complex, resulting in the formation of amorphous form. Furthermore, the SAS-processed RV/ HP-β-CD powders showed a significant enhancement in the solubility of RV (up to 25.13 mg/mL) in an aqueous medium. The percent dissolution of RV increased considerably and about 100% of RV was dissolved within 5-10 min. © 2011 Wiley Periodicals, Inc.