FORMULATION AND EVALUATION OF BILAYER TABLETS BEARING FLOATING PMMA MICROSPHERES OF BACLOFEN AND RABEPRAZOLE SODIUM
Tony M. Kuriakose* and Dr. Arun Raj R.
The present study aims at formulation, optimization and characterization of floating Poly Methyl Methacrylate (PMMA) microspheres of Baclofen and Rabeprazole sodium and to formulate into a bilayer tablet for the management of multiple sclerosis and persistent hiccups. Here, both the drugs are having short biological half-life which limits their therapeutic potential. Gastro Retentive Floating Drug Delivery System is used for increasing gastric residence time of the drugs. Due to its high biocompatibility, PMMA is a widely used polymer. Baclofen and Rabeprazole sodium microspheres were prepared separately by o/w solvent evaporation method. The prepared microspheres of baclofen and rabeprazole sodium were characterized forits percentage entrapment efficiency, percentagebuoyancy, percentage in-vitro drug release profile, Scanning electron microscopy study and differential scanning calorimetry. Nine formulations each of baclofen (FB1-FB9) and rabeprazole sodium (FR1-FR9) floating microspheres were prepared according to the response surface 3 level factorial design by Design expert 11 trial version. Based on statistical evaluation of Software suggested one optimum batch each for Baclofen and rabeprazole sodium floating PMMA microspheres. The Optimized microspheres of baclofen and rabeprazole sodium were evaluated and formulated into bilayer tablet by direct compression. Sustained release layer of baclofen showed an in-vitro drug release of 77.4% and that of rabeprazole sodium exhibited an in-vitro drug release of 79.7% in 0.1N HCl at the end of 8th hour in-vitro dissolution study. In-vivo floating study of the formulated bilayer tablet was performed in New Zealand rabbit for 6 hours and was well retained in the stomach.
Keywords: Baclofen, Rabeprazole sodium, Floating PMMA microspheres, Bilayer tablet, Multiple sclerosis, Persistent hiccups.
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