Abstract
The present investigation was aimed at formulation of multiple unit oral gastroretentive floating drug delivery system of ranitidine to prolong the gastric residence time, target stomach mucosa and increase bioavailability. Effervescent calcium alginate beads were prepared by ionotropic gelation technique using different proportions of sodium alginate, hydroxyl propyl methyl cellulose and sodium bicarbonate. Olive oil entrapped beads were also prepared by emulsion gelation method and concentration of oil was optimized. The developed beads were evaluated for mean diameter, surface morphology, floating lag time, buoyancy, entrapment efficiency and in vitro drug release. The optimized formulation of olive oil entrapped microbeads exhibited longer duration of floating time and greater entrapment efficiency than the effervescent formulations. The in vitro release studies in simulated gastric fluid (pH 1.2) indicated that, for optimized formulation (F8); at the end of 8hours, 93% of the entrapped amount of drug was found to release with promising floating characteristics. The drug release data were fitted to release kinetic equations and accelerated stability studies were performed for optimized batch.
