Solubility enhancement of celecoxib using β-cyclodextrin inclusion complexes

Abstract

Celecoxib has very low water solubility. It forms a complex with β-cyclodextrin (βCD) both in aqueous and in solid state. It was observed that due to formation of the inclusion complex, the solubility and dissolution rate of celecoxib were enhanced. The formation of 1:1 complex with βCD in solution was confirmed by phase solubility and spectral shift studies. The apparent stability constants calculated by these techniques were 881.5 and 341.5 M −1, respectively. The solid inclusion complexes of celecoxib and βCD were prepared by the kneading method using different molar proportions of βCD, and formation of solid inclusion complexes of celecoxib and βCD at different molar ratios were confirmed by differential scanning calorimetry. Enhancement of dissolution rates with increasing quantity of βCD in the complex was observed. It was also observed that the complexes exhibit higher dissolution rates than the pure drug and physical mixture.