Sustained release formulation and characterization of nifedipine three-layered tablet using various polymers

Nifedipine is mainly used for treatment of antianginal (especially in Prinzmetal's angina) and antihypertensive. However, it is needed to improve the dissolution rate because it is poorly water-soluble drug. Nifedipine needs the sustained release formulation due to its short half-life of 1.5∼2 h. Therefore, the purpose of this study is to control the burst release of nifedipine through the multi-layer as three layers formulation for 24 h. Upper and bottom layers consisted of gel-forming polymers as release controlling agent, and the middle layer was prepared by nifedipin-PVP K30 solid dispersion. The prepared solid dispersion was analyzed by SEM, XRD and DSC. The prepared multi-layer tablet was characterized by swelling assays. The release behavior of nifedipine from the multi-layer tablet was confirmed through in vitro assay (pH 6.8). It was confirmed that the nifedipine three-layered tablet using hydroxypropylmethyl cellulose (HPMC) K15M showed the best of sustained pattern and dissolution behavior.