Efficiency of cyclodextrin-ibuprofen inclusion complex formation

A modified method for ibuprofen/beta-cyclodextrin (IBU/beta-CD) complex formation, based on ball milling (BM) under controlled conditions was developed and its efficiency with respect to the drug encapsulation yield was compared with the well-known kneading and solid dispersion synthetic approaches. Quantitative evaluation of the efficiency of drug-cyclodextrin interaction applying various methods and experimental conditions as well as characterization of the inclusion complexes were carried out by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetry (TG), scanning electron microscopy (SEM), infrared (IR) and nuclear-magnetic resonance ((HNMR)-H-1) spectroscopy. It was found that the yield of the formed IBU/beta-CD complex varies in a large range, depending on the techniques applied. The degree of complexation between IBU and beta-CD using the proposed optimized BM method is very high and close to the complete inclusion complex formation achieved by a modified solid dispersion method. Furthermore, using DSC, TG and (HNMR)-H-1 we proved that the ibuprofen molecules enter the beta-CD hydrophobic cavities replacing completely the water molecules present naturally inside, which we determined to be 7. (C) 2016 Published by Elsevier B.V.