DEVELOPMENT AND EVALUATION OF SUSTAINED RELEASE BILAYER MATRIX TABLET OF GLIPIZIDE AND METFORMIN HYDRO CHLORIDE

The ultimate aim of the present study was to develop sustained release bilayer matrix tablet formulation that contains both glipizide & metformin HCl such that it can provide synergistic effect for the therapeutic Management of diabetes. Bilayer tablet was formulated to develope and determine the sustained release effect of both Glipizide and Metformin Hydrochloride using various polymers as hydroxyl propyl methyl cellulose K15 M, Hydroxy Ethyl Cellulose and Ethyl cellulose etc. at different concentration. The influence of varying the polymer/polymer (w/w) ratio was evaluated. The excipients used in this study did not alter physicochemical properties of the drug, as tested by Fourier transform Infrared Spectroscopy. All the batches were evaluated for thickness, weight variation, hardness, and drug content uniformity. The in vitro drug dissolution study was carried out using USP 22 apparatus II, paddle method and the release mechanisms were explored. Mean dissolution time and regression values were determined to characterize the drug release rate from a dosage form and helped to indicate the drug release retarding efficiency of the polymer used. Kinetic modelling of in vitro dissolution profiles revealed the drug release mechanism ranges from diffusion controlled to anomalous type. Keywords Bilayered tablet, Matrix tablet, Glipizide, Metformin Hydrochloride, Hydroxy Propyl Methyl Cellulose and Ethyl Cellulose.