Solid state characterization of trans resveratrol complexes with different cyclodextrins
Author: Mont Kumpugdee-Vollrath, Yvonne Ibold, Pornsak Sriamornsak
Category: Pharmacy
Abstract:
Trans resveratrol (Res) has been investigated numerously because of having interesting pharmacological effects but Res has low bioavailability. As the solubility, stability and bioavailability of a drug can be increased by a complexation with cyclodextrin (CD), it was herein to prepare Res–CD complexes and their physical mixtures different types of CD. In order to understand the solid state behavior, various characterization techniques were applied. The results from differential scanning calorimetry showed double peaks at 254°C and 269°C, demonstrating the melting point of pure Res. Most of the pure CDs decomposed over 300°C. Beta-CD and 2- hydroxypropyl-beta-CD had a significant peak around 100°C which demonstrated the evaporation of water. Alpha-CD had many peaks between 80-140°C and also 269°C which differed from dimethyl-beta-CD. Res– alpha-CD complex showed peaks at 130°C and 269°C, whereas Res–beta-CD only showed peak at 269°C. The modified CDs did not show the significant peak of Res or water. This indicated that Res replaced water in the cavity and a real inclusion complex was formed. The infrared spectra also confirmed the formation of complex. The small and wide angle X-ray scattering patterns showed the difference of Res, CD and different complexes.
Keywords: solid state resveratrol cyclodextrin IR DSC SWAXS
