Influence of Coating Formulation and Preparation of Acetaminophen Sustained-release Pellets on the Drug Release

OBJECTIVE To study the influence of coating formulation and preparation of membrane controlled release pellets on its release profile in vitro. METHODS Acetaminophen pellets were prepared by means of liquid layering with the centrifugal granulation equipment. The single factor experiments and orthogonal design were applied to optimize the formulation of coating solution and the technical parameter. The release mechanism of coated pellets was studied by fitting with different release models. RESULTS The optimal drug sustained-release was showed at the ratio of Eudragit RS PO to RL PO of 10∶1, loading weight of copolymers of 10% and polymer concentration of 6%. The drug release from coated pellets was primarily promoted by osmotic pressure and skeleton dissolution also played a certain synergy. CONCLUSION The acetaminophen membrane controlled release pellets prepared by centrifugal granulation equipment are uniformly coated, easy to be operated, which has reliable quality, and can be a industrial production.