In vitro study of gastrointestinal diffusion system using disopyramide phosphate.

Gastrointestinal Diffusion System (GDS) provides release of a drug by means of a controlled source of diffusion energy. The unit can possibly be used for all soluble agents in which solubility is independent of the pH of the gastrointestinal contents as is the case with disopyramide phosphate. The GDS consists of a soluble tablet-core, surrounded by a cellulose acetate film containing a soluble pore-creating agent. When the pore-creating agent is removed from the coating film, the cellulose acetate membrane which remains is of a porous nature, which controls the diffusion rate of the drug. The release rate of the drug can be varied by changing the composition and mass of the membrane. The resultant system in vitro provides the zero-order drug delivery due to the appropriate selection of manufacturing parameters.