Sustained release microspheres containing phenylpropanolamine HCl (PPA) were prepared with acrylic polymer (Eudragit RL/RS) sand hydroxypropylmethylcellulose phthalate (HPMCP) using a emulsion-solvent evaporation method. Magnesium stearate was used a smoothing agent for preparation of microspheres. The microspheres obtained were very spherical and free-flowing particles. Scanning electron microscopy showed that microspheres have a smooth surface and a sponge-like internal structure. The dissolution rate of PPA from the microspheres was dependent on the pH of dissolution media. PPA showed faster release in pH 1.2 solution than in pH 7.4 solution due to the solubility of PPA. Therefore we prepared new microspheres containing 5% (w/v) HPMCP in order to control the release of PPA. The release rate of PPA from these new microspheres was similar in pH 1.2 and pH 7.4 solution.
All Science Journal Classification (ASJC) codes
- Molecular Medicine
- Drug Discovery
- Organic Chemistry