Effect of polyvinylpyrrolidone on complexation and dissolution rate of β- and hydroxypropyl-β-cyclodextrin complexes of celecoxib

Complexation of celecoxib with β-cyclodextrin and hydroxypropyl-β-cyclodextrin in the presence and absence of polyvinylpyrrolidone and the effect of polyvinylpyrrolidone on the solubilizing efficiency of cyclodextrins and on the dissolution rate of celecoxib from the cyclodextrin complexes were investigated. The phase solubility studies indicated the formation of celecoxib-β-cyclodextrin and celecoxib-hydroxypropyl-β-cyclodextrin inclusion complexes at a 1:1 M ratio in solution, both in the presence and absence of polyvinylpyrrolidone. The complexes formed were quite stable. The solubility and dissolution rate of celecoxib were markedly enhanced by complexation with β-cyclodextrin and hydroxypropyl-β-cyclodextrin. Celecoxib-hydroxypropyl-β-cyclodextrin (1:2) inclusion complex gave a 36.57-fold increase in the dissolution rate of celecoxib. Addition of polyvinylpyrrolidone resulted in higher complexation efficiency and markedly enhanced solubilizing efficiency of β-cyclodextrin and hydroxypropyl-β-cyclodextrin. Solid inclusion complexes of cyclodextrins with polyvinylpyrrolidone gave several times higher rates of dissolution than those of celecoxib and its complexes with cyclodextrins alone.