2-HYDROXYPROPYL-BETA-CYCLODEXTRIN COMPLEXATION WITH URSODEOXYCHOLIC ACID

The complexation in aqueous medium and in the solid phase of ursodeoxycholic acid (UDCA) with a highly soluble cyclodextrin, 2-hydroxypropyl-beta-cyclodextrin, was studied by means of solubility methods, IR and C-13-NMR spectroscopy, X-ray diffractometry and thermal analysis. UDCA inclusion took place with 1:1 stoichiometry. C-13-NMR analysis suggested that the side chain was introduced into the cyclodextrin cavity. The UDCA/cyclodextrin complex showed better dissolution properties than plain drug crystals. Therefore, the complex may be used to improve the delivery and bioavailability of ursodeoxycholic acid.