DESIGN AND OPTIMIZATION OF MULTIPARTICULATE GASTRORETENTIVE DELIVERY SYSTEM OF RANITIDINE HYDROCHLORIDE

In the present study, a gastroretentive Microparticulate system of an anti-ulcer drug Ranitidine hydrochloride, capable of floating on simulated gastric fluid for more than 24 hours was formulated by solvent evaporation technique. Eudragit RL-100, a biocompatible polymer was used to form microspheres of Ranitidine hydrochloride by response surface methodology. The formulated microspheres were characterized for their micromeritic properties, surface morphology by SEM and optical microscopy, drug-polymer compatibility studies by FTIR and DSC, in-vitro buoyancy studies, percentage drug entrapment efficiency and in-vitro drug release studies. Optimization studies were carried out by taking RPM (stirring speed) and amount of polymer as independent variables and percentage drug entrapment and time taken to release 90% drug ( t90% ) as responses using 3-level factorial design. The formulated microspheres free flowing and SEM studies indicated that the microspheres were porous and almost spherical in shape. The prepared microsphere formulations having percentage drug entrapment of 83.40- 85.24%, and buoyancy of 86.42 -95.58% with floating time up to 12 hours. In-vitro drug release studies of Ranitidine hydrochloride microspheres showed a controlled release of 11 hours with Eudragit RL-100. The data obtained in this study thus suggest that a Microparticulate floating dosage form of an anti-ulcer drug can be successfully designed to give controlled drug delivery and improved oral bioavailability.