Ethyl cellulose and hydroxypropyl methyl cellulose buoyant microspheres of metoprolol succinate: Influence of pH modifiers.

Introduction: Incorporation of pH modifier has been the usual strategy employed to enhance the dissolution of weakly basic drug from floating microspheres. Microspheres prepared using a combination of both ethyl cellulose (EC) and hydroxypropyl methylcellulose (HPMC) which shows highest release were utilize to investigate the effect of fumaric acid (FA), citric acid (CA), ascorbic acid (AA) and tartaric acid (TA) (all 5-20% w/w) incorporation on metoprolol succinate (MS) release.

Materials And Methods: EC, HPMC alone or in combination were used to prepare microspheres that floated in simulated gastric fluid and evaluated for a percent yield, drug entrapment, percent buoyancy and drug release.

Eudragit-S, Eudragit-L and cellulose acetate phthalate coated polysaccharide tablets for colonic targeted delivery of azathioprine.

The present work deals with the formulation and evaluation of polymer-coated polysaccharide tablets of azathioprine prepared by direct compression method using different ratios of avicel (MCC), inulin and triacetin. The tablets formulations containing 25 mg of azathioprine were prepared and evaluated for thickness, hardness, friability, weight variation, content uniformity and in vitro dissolution test. Hardness and percentage friability were in the range of 7.