Effect of Polyvinylpyrrolidone on Complexation and Dissolution Rate of Beta Cyclodextrin and Hydroxypropyl Beta Cyclodextrin Complexes of Piroxicam

Complexation of Piroxicam with β-Cyclodextrin and hydroxypropyl-β-Cyclodextrin in the presence and absence of polyvinylpyrrolidone and the effect of polyvinylpyrrrolidone on the solubilizing efficiency of Cyclodextrins and on the dissolution rate of Piroxicam from the Cyclodextrin complexes were investigated. The phase solubility studies indicated the formation of Piroxicam-β-Cyclodextrin and Piroxicam-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 Piroxicam were markedly enhanced by complexation with β-Cyclodextrin and hydroxypropyl- β-Cyclodextrin. Piroxicamhydroxypropyl-β-Cyclodextrin(1:2) inclusion complex gave a 36.52-fold increase in the dissolution rate of Piroxicam. 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 Piroxicam and its complexes with Cyclodextrins alone.