Formulation and In-vitro evaluation of sustained release matrix tablet of Metformin hydrochloride

Abstract

The low bioavailability and short half-life of Metformin hydrochloride (MH) make the development of sustained-release forms desirable. Present work involves preparation and optimization of sustained release matrix tablet of MH by direct compression method using HPMC K 100 and ethyl cellulose as a matrix forming polymer. Avicel was added as a direct compaction vehicle to improve the compaction behavior of Metformin which otherwise exhibits poor compaction behavior which again is further increased by its relatively high dose. Hydrophilic matrix of HPMC alone resulted in initial burst of Metformin release, however when combined with ethyl cellulose drug release was slowed down and thereafter it became optimal at particular concentration of polymers. Keywords:  Metformin, HPMC, Ethyl cellulose, sustained release, matrix, tablet.