Improvement in the percutaneous absorption of beclomethasone dipropionate by γ-cyclodextrin complexation

Abstract

Inclusion complex formation of beclomethasone dipropionate (BMDP) with γ-cyclodextrin (γ-CyD) in water and in solid state was assessed by solubility analysis and X-ray diffractometry. The solid complex of BMDP with γ-CyD in a molar ratio of 1:2 was prepared and its in-vitro release behaviour was investigated using an ointment release simulator. The release of BMDP from hydrophilic ointment was significantly improved by the γ-CyD complexation. Permeation and uptake studies indicated that the enhanced release of BMDP from the ointment may be due to the faster dissolution and the lower binding affinity of the complex in the ointment base. The vasoconstrictor activity of BMDP in man was found to be increased by γ-CyD complexation, suggesting an improvement in the percutaneous absorption of BMDP.