DISSOLUTION KINETICS FOR COPRECIPITATES OF DIFLUNISAL WITH PVP K30

Diflunisal is a nonsteroidal anti-inflammatory drug that is poorly sol uble in water. The present study describes the formulation of solid di spersions of the drug designed to increase its solubility. X-ray diffr action and DSC were used to examine the physico-chemical characteristi cs of solid dispersions of diflunisal and polyvinylpyrrolidone (PVP) p repared by the solvent method, using percentage proportional compositi ons ranging from 20:80 to 50:50. X-ray diffraction analysis detected t hat diflunisal is present in solid dispersions in crystalline or amorp hous state depending on the PVP content. The thermal behavior of diflu nisal observed in the DSC curves of solid dispersion systems, was attr ibuted to a solid-state interaction. The increased release of the PVP- drug dispersion as compared to the PVP-drug physical mixture was attri buted to the formation of a complex resulting from the interaction of the drug and the polymer.