PHYSICAL CHARACTERISTICS AND DISSOLUTION KINETICS OF SOLID DISPERSIONS OF KETOPROFEN AND POLYETHYLENE-GLYCOL-6000

The formation of solid dispersions is an effective method of increasing the dissolution rate of poorly soluble drugs, and hence, of improving their bioavailability. We used the dissolution method to prepare solid dispersions of ketoprofen and polyethylene glycol 6000 (PEG 6000), and compared the dissolution kinetics of the dispersions with physical mixtures and pure drug. Physicochemical characteristics were determined by X-ray diffractometry and differential scanning calorimetry. Drug/polymer mixtures containing up to 50% ketoprofen formed eutectic compounds. The results of dissolution kinetics studies showed that PEG 6000, when used as a carrier for solid dispersions, increased the dissolution rate of ketoprofen. The t(80%) of dissolution for pure drug (88.5 min) decreased to 1.9, 4.0 and 22.5 min, respectively, in solid dispersions containing 10:90, 50:50 and 90:10 proportions of ketoprofen/PEG 6000. We conclude that the 10:90 solid dispersion displays the best dissolution kinetics of those tested.