Solubility of Diclofenac Acid Form from Solid Dispersions

The influence of solid dispersions (SD) on diclofenac solubility was determined by studying diclofenac (acid form) and its SD with polyethyleneglycol-1500 (PEG) and polyvinylpyrrolidone-10000 (PVP). SD formation increased the solubility and dissolution rate of the non-steroidal anti-inflammatory drug (NSAID). Diclofenac solubility from the SD with PVP increased by 2.5 times; from the SD with PEG (solvent evaporation method), by 8 times compared with diclofenac drug substance. A combination of physicochemical methods showed that the improved release of diclofenac from the SD occurred because of reduced crystallinity, formation of drug solid solutions in the polymer matrix, and formation of a colloidal drug solution. © 2015, Springer Science+Business Media New York.