Characterization and intrinsic dissolution rate study of microwave assisted cyclodextrin inclusion complexes of gemfibrozil

Abstract

Objective: The aim of the present study was to carry out characterization and intrinsic dissolution rate study of microwave assisted inclusion complex of poorly water soluble, lipid lowering agent gemfibrozil [5-(2,5-dimethylphenoxy)-2,2-dimethylpentanoic acid] with naturally occurring β-cyclodextrins (CDs) or cycloheptaamylase. Methods: In this work, the phase solubility study was performed to find the ratio of drug and cyclodextrin complexes. Inclusion complexes were prepared by kneading and the prepared complex was subjected to microwave drying and conventional drying techniques. The prepared complexes were evaluated by intrinsic dissolution rate studies and equilibrium solubility study. Further characterization was done by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray powder diffractometry (DSC). Results: The phase solubility studies showed a linear AL-type diagram indicating the formation of inclusion complexes in 1:1 molar ratio β-CD-gemfibrozil complex with maximum stability constant of 148.88 M-1was selected for preparation of inclusion complex. The microwave dried product was identified as the inclusion complex with maximum IDR when compared to the conventional dried product. Conclusion: This study was concluded that the microwave drying is the most suitable of the previously occurring drying techniques. Since it showed the highest solubility and IDR value.