Preparation and Evaluation of Bi-layer Captopril as Sustained Release and Amlodipine Besylate as Immediate Release Tablet

The present study was carried out in order to develop bi-layer tablet to achieve immediate and the sustain release were prepared by direct compression method. The Immediate release layer prepared by using superdisintegrant Sodium starch glycolate, Cross povidone, and Cross carmellose sodium with three different concentrations. Cross carmillose sodium was selected for preparation of bi-layer tablet. The sustained release layer prepared by using polymers Sodium alginate, HPMCK15, Carbapol 940, Xanthum gum in three different concentrations. HPMCK15 was selected for preparation of bi-layer tablet. APIs, blends were performed preformulation studies such as incompatibility studies, solubility, bulk density, tapped density, Carr's index, Hausner's ratio and angle of repose which would really support to formulate efficient bilayer tablets. The bilayer tablet were investigated such as weight uniformity, hardness, drug content, in vitro dissolution study, In vitro buoyancy study, Kinetic data analysis Batch F13 optimized by using 32 factorial designs for the % drug release and floating lag time. From the post optimization analysis of the bi-layer tablet, the optimized batch showed 76.40% release of Captopril as a sustained release within 8hrs and 96.7% release of Amlodipine Besylate as Immediate release after 1hr. Floating lag time was found to be 110sec. From drug release kinetics, optimized F4 Captopril layer follows Higuchi Matrix Model. having higher correlation coefficient r2 0.9594.