Eudragit E, L and S (acrylic resins) microcapsules as pH sensitive release preparations of ketoprofen

Microencapsulation of ketoprofen using Eudragit E, L and S (acrylic resins) was investigated. The preparation is based on the dispersion of acetone containing ketoprofen in liquid paraffin. Aluminium tristearate was used as an additive for the preparation of microcapsules. In the preparation of microcapsules, the reproducibility of the Eudragit E microcapsule was better than that of Eudragit L and S microcapsules. The microcapsules obtained were uniform and free-flowing particles. From the phase diagram of ketoprofen-Eudragit E or S-aluminium tristearate, it became clear that the region in which the spherical microcapsules ranging from 250 to 1000 microns in size could be prepared was limited. The dissolution patterns of ketoprofen from Eudragit E, L and S microcapsules were dependent on the pH of the dissolution medium.