¹Department of Pharmaceutical Technology, Faculty of Pharmacy, Gazi University, Ankara, Turkey
²Department of Pharmaceutical Technology, Gulhane Faculty of Pharmacy, University of Health Sciences, Ankara, Turkey DOI : 10.29228/jrp.10 Flurbiprofen (FB) is one of the nonsteroidal anti-inflammatory drugs with poor water solubility. Cyclodextrins have a special structure (hydrophobic inner phase and hydrophilic outer phase), which have been widely used to enhance the solubility and stability of drug substances in pharmaceutical applications. The present study is intended to improve the solubility of FB with the inclusion complexes assembled by using beta-cyclodextrin (β-CD) and hydroxypropyl beta-cyclodextrin (HPβ-CD) and to perform the phase solubility studies to estimate the stability constant and complexation efficiency. The results of phase solubility studies showed that the FB/β-CD complexes have Bs type and FB/HPβ-CD complexes have AL type profiles in both PBS and water media. The interaction forces between FB and HPβ-CD were stronger than FB and β-CD for the formation of inclusion complex in water. Moreover, the complexation efficiency value of FB/HPβ-CD complex in water media was found higher than the FB/HPβ-CD complex in PBS media. These results of phase solubility studies absolutely demonstrated the advantage of HPβ-CD instead of β-CD to obtain the inclusion complex with 1:1 Molar ratio in water and to improve the apparent water solubility of FB. According to these results, the FB/HPβ-CD inclusion complex was prepared with the Freeze-drying method and it was achieved to enhance the water solubility of FB 52.6-fold with using HPβ-CD. In conclusion, the presence of the inclusion complex was successfully confirmed by differential scattering calorimetry, X-ray diffraction, scanning electron microscopy and fourier transform infrared analysis. Keywords : Flurbiprofen; phase solubility; cyclodextrins; inclusion complex; freeze-drying