Résumé
Purpose To build up the Potassium Sodium Dehydroandroan Drographolide Succinate enteric coating sustained-release pellets delivery system by aqueous dispersion coating technique. Methods 1. Adopting MCC as vehicle, SiO_2 as antisticking agent, appropriate amount of 40% ethanol, preparing the core of pellets by extrude-spheronization method and the formulation and manufacturing process were optimized by orthogonal design. 2. Preparing the coating material with Eudragit L 30 D, which is used as pore-forming agent, EC as blocker and PEG6000 as plasticizer. The pellets were coated by fluid-bed coating method. Results 1. The optimal formulation and manufacturing process of pelltes' core were as follows: drug: MCC: SiO_2 = 7:7:5, extruding rate: 1 080 r/min, rounding rate: 960 r/min, rounding time: 5 min. 2. After the addition of EC: Eudragit L = 35:65, the plasticizer is 1.71 % and weight gain is 5% . The release in the gastric model fluid(pH 1.0) < 10% , and complete release ( > 80% ) in the enteric model fluid(pH 6.8) was in two hours. The release behavior accords with the regulations on the release rate of enteric preparation in ChP. Conclusion By adjusting the formulation and the parameters of the process of pellet and coating, we can make enteric coating Potassium Sodium Dehydroandroan Drographolide Succinate sustained-release pellets. All this accords with the regulation of pharmacopedia in vitro release.