Abstract
The aim of present study involves preparation and characterization of floating microspheres using trimetazidin dihydrochloride as a model drug to increase the residence time in the stomach without contact with the mucosa, Floating microspheres were prepared by the capillary extrusion technique using chitosan as polymer and sodium lauryl sulphate as cross linking agent. The surface morphology of the prepared microspheres was characterized by the optical microscopic method. The effect of the stirring rate during preparation, polymer concentration and cross linking concentration on the percent yield, in vitro floating behavior, physical state of the incorporated drug, drug loading and in vitro drug release were studied. The prepared microspheres exhibited prolonged drug release (12 h) and remained buoyant for more than 11 h. The microspheres were found to be regular in shape and highly porous. The trimetazidin dihydrochloride release rate was higher in the case of microspheres prepared at a higher agitation speed and decreased with increasing the polymer and cross linking agent concentration. All formulations demonstrated favorable in vitro floating characteristics. The drug entrapment increased from 65.13 to 85.3% with increasing polymer to drug ratio. Diffusion was found to be the main release mechanism. Thus, the prepared floating microspheres may prove to be potential candidates for multiple-unit delivery devices adaptable to any intragastric conditions.