The effect of sodium alginate on physical and dissolution properties of Surelease®-matrix pellets prepared by a novel pelletizer

Abstract

The aim of this study was to investigate the effect of sodium alginate on the physical and dissolution properties of Surelease®-matrix pellets prepared by a novel pelletizer-equipped piston extruder and double-arm counter-rotating rollers. The mean values of the shape factor (eR) and the aspect ratio of Surelease®-matrix pellets were 0.615-0.625 and 1.06-1.070, respectively, indicating good sphericity of the pellets. The drug release rate increased as the amount of sodium alginate increased due to hydration, swelling, and erosion within the Surelease®-matrix pellets. In addition, the porosity of pellets also increased with increasing sodium alginate content. The results of this study show that sodium alginate has a greater effect on the drug release rate than the drug release mechanism within the Surelease®-matrix for sparingly water-soluble drug, such as tamsulosin hydrochloride. © 2007 Pharmaceutical Society of Japan.