The aim of this study was to prepare and evaluate the pellets, containing a highly soluble drug (ascorbic acid), by the extrusion-spheronization process and coated with a release controlling polymer. The coating (undertaken in a fluid bed) was applied to three batches of the pellets with a dispersion of Kollicoat® SR 30 D, with each batch of pellets receiving a different level of polymer (5.07; 8.26 and 10.35%). The coated pellets were evaluated for sphericity by imaging analysis and comparative dissolution profile with a product commercially available in Brazil. All of the evaluated samples presented adequate physical properties and the dissolution profile of those coated with 5.07% of polymer proved to be similar to that of the commercially available...
Dextromethorphan hydrobromide (DM) sustained release matrix pellets containing 10% w/w drug were prepared by an extrusion/spheronization technique. The effect of mixing different concentrations of ethyl cellulose (EC), hydroxypropyl methylcellulpse (HPMC K10), and Carbopol 934 with Avicel PH101 on the rheological properties of pellet wet mass was evaluated using mixer torque rheometry (MTR). The prepared pellets were characterized for size, drug content, and in-vitro DM release rate. The results showed that increasing the concentration of the hydrophobic polymer (EC) with Avicel PH101 decreased wet mass consistency, represented by mass mean line torque. Lower binder ratio was required for optimum wet massing, while mixing with swellable polymers (HPMC and...
