Studies on Delayed-release Enteric Film Using Blends of Aqueous Dispersion

OBJECTIVE To prepare new polymer film using blends of enteric Eudragit?L30D-55 and sustained-release Kollicoat?SR30D which can provide drug delayed-release profiles that triggered by the pH of the surrounding environment along the gastrointestinal tract. METHODS Free film of polymer blends was prepared by casting technique. Properties of the cast film including glass transition temperature(Tg), mechanical properties and permeability were investigated. Effect of polymer blend ratio and additive on properties of the cast film was evaluated. Pantoprazole sodium(PAZ-Na) was selected as a model drug to prepare delayed-release enteric pellets. RESULTS With an increasing content of SR30D, properties of the cast films varied Tg decreased; strength and stiffness of film weakened, tenacity enhanced; water vapor permeability remained at a certain level firstly, and then increased. With an increasing amount of plasticizer, stiffness of free film weakened and water vapor permeability increased. With the addition of insoluble additive, water vapor permeability decreased at different level. Less than 5% drug degradation occurred after pellets exposed to 0.1 mol·L^-1 HCl solution for 2 h. The delayed-release enteric pellets began to release the drug after 10-20 min and released completely after 90 min in phosphate buffer of pH 6.8. CONCLUSION Free film and coating of polymer blends offers favorable physical characteristics. Blends of aqueous dispersion of Eudragit?L30D-55 and Kollicoat?SR30D can be used for R&D of modified-release enteric preparations.