Formulation and Development of Bilayer Floating Tablet of Nifedipine using surface solid dispersion technique

Abstract

The aim of the present work was to develop formulation of Nifedipine in the form of bilayer floating sustained release tablet. Bilayer consist of a two layers, immediate release layer and second sustained release layer, compressed in single unit dosage form. Immediate release layer contains surface solid dispersion of Nifedipine and Floating sustained release layer also contain surface solid dispersion of Nifedipine by using HPMC K100M and HPMC K15M as sustained release polymer. Nifedipine is an antihypertensive drug. Surface solid dispersion of Nifedipine was prepared by solvent evaporation method with different super disintegrant as a polymer for improvement of solubility resulting in improved bioavailability. In the present study Nifedipine bilayer floating controlled release tablet were prepared with the help of direct compression method, using sodium bicarbonate and citric acid which generate gas upon contact with gastric fluid. Immediate release layer releases the drug immediately and floating sustained release layer floats on gastric fluid for upto12 hours and releases the drug in sustained manner, subsequently it prolongs duration of action. The tablets were evaluated for various physical parameters, buoyancy studies, dissolution studies and drug released mechanisms. The batch number F5 formulation showed minimum disintegration time of immediate release layer (24 sec) and gave maximum swelling index of the sustained release layer (82.8%) and also maximum drug release duration of Nifedipine spread over 12 hours.