Preparation and in vitro evaluation of altered density gastro retentive microspheres of Famotidine with synthetic and natural polymers

The main aim of the present work was to fabricate and evaluate gastro retentive high density microspheres with both synthetic and natural polymers for the sustained release of Famotidine to treat gastric ulcers. The microspheres were prepared by the coacervation phase separation technique. Famotidine was checked for its compatibility with polymers used by using Fourier Transform Infrared spectroscopic (FTIR) analysis. The surface morphology was studied by scanning electron microscopic (SEM) studies. The percentage of yield, surface associated drug content, drug entrapment efficiency and in vitro dissolution studies were performed and the dissolution data was treated with mathematical kinetic models. Accelerated stability studies were also carried out to the optimized formulation (F-6). The FTIR spectrum of pure drug and drugpolymer blend showed the stable character of Famotidine in the micro capsules. The microspheres were found to be spherical. The microspheres had good entrapment efficiency and percentage yield. The release of drug from the microspheres extended up to 12 h. The release kinetics data and characterization studies indicate that drug release from microspheres was diffusion sustained and that the microspheres were stable. The study revealed that Gellan gum and Karaya gum in combinations with Povidone found to be effective combination for microspheres and the gastric retention was aided with Iron oxide.