Interaction of ibuprofen with β-cyclodextrins : Experimental and molecular modeling studies

The aim of this work was to study the interaction of beta-cyclodextrin and its chemically modified varieties (hosts) with ibuprofen (guest). For this purpose the physicochemical characterization of host-guest binary systems were carried out by UV-Visible (UV-Vis), Fourier transform infrared (FTIR) spectroscopy and quantum mechanical semi empirical PM3 calculation. UV-Vis and FTIR studies revealed inclusion complex formation and PM3 calculations correlated with the experimental findings. The adsorption of ibuprofen in aqueous solutions onto beta-cyclodextrin-bonded silica phase (CDS) was also investigated with the aim of an in-depth understanding of the host-guest interaction. The kinetic behaviour of ibuprofen adsorbed on CDS revealed that the rate-limiting step may be chemical adsorption, which confirmed that adsorption of ibuprofen takes place via inclusion complexation. Scanning electron micrographic (SEM) studies showed morphological differences in the unloaded adsorbent and the changes in the adsorbed CDS.