Insights to the phase solubility diagrams of flurbiprofen with inclusion complex

Oktay A. N.

JOURNAL OF RESEARCH IN PHARMACY, vol.25, no.2, pp.196-208, 2021 (ESCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 25 Issue: 2
  • Publication Date: 2021
  • Doi Number: 10.29228/jrp.10
  • Journal Indexes: Emerging Sources Citation Index (ESCI), Scopus, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.196-208
  • Gazi University Affiliated: Yes


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 (beta-CD) and hydroxypropyl beta-cyclodextrin (HP beta-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/beta-CD complexes have B-s type and FB/HP beta-CD complexes have A(L) type profiles in both PBS and water media. The interaction forces between FB and HP beta-CD were stronger than FB and beta-CD for the formation of inclusion complex in water. Moreover, the complexation efficiency value of FB/HP beta-CD complex in water media was found higher than the FB/HP beta-CD complex in PBS media. These results of phase solubility studies absolutely demonstrated the advantage of HPP-CD instead of beta-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/HP beta-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 HP beta-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.