PREPARATION AND EVALUATIONOF IN-VITRO RELEASE KINETICS OF NOVEL BILAYER METOPROLOL SUCCINATE AS SUSTAINED RELEASE AND AMLODIPINE BESYLATE AS IMMEDIAT RELEASE TABLETS
The present study was to establish biâ€layer tablets containing Metoprolol succinate as sustained release and Amlodepine besylate as immediate release layer. APIs, blends and granules were performed preformulation studies such as incompatibility studies, solubility, LOD, bulk density, tapped density, Carr’s index, Hausner’s ratio and angle of repose which would really support to formulate efficient bilayer SR tablets. Sustained layer (Metoprolol succinate) were prepared by wet granulation method using different viscosity grade of HPMC (HPMC K4M & HPMC K100M) as polymers and immediate release layer (Amlodipine besylate) were prepared by direct compression method using super-disintegrant crosscarmellose sodium. Fabricated tablets was investigated such as weight uniformity, hardness, friability, disintegration, drug content, in-vitro swelling studies, in-vitro dissolution study, stability studies and kinetic data analysis. In-vitro release studies were carried out by USP typeâ€I basket apparatus with 50 rpm for 1, 4, 8, and 20h using phosphate buffer pH = 6.8. The obtained results were clearly indicating that the formulated tablets results are within the range and when compared with all formulations F6 and F4 were sufficiently sustained (96.86%), immediate release (95.4%) for 20h and 56s respectively. Kinetic study has showed that sustained release of drug was anomalous non-fickian transport, diffusion and obeys zero order release from the formulation was observed. The present study has shown that formulation F6 (drug: polymers 1:1.5:0.33) was found to be acceptable limit as it exhibits drug release pattern very close to the theoretical release profile. The results showed that combinations of polymers namely HPMC K100M and HPMC K4M in sustained layer can control the release of drug.