He P, Davis S S, Illum L
Department of Pharmaceutical Science, University of Nottingham, UK.
J Microencapsul. 1999 May-Jun;16(3):343-55. doi: 10.1080/026520499289068.
Modified spray drying methods, especially a novel w/o/w emulsion-spray drying method, were developed to prepare chitosan microspheres with a sustained drug release pattern. Release of the model drugs cimetidine and famotidine, from the microspheres prepared by the emulsion-spray drying methods, was greatly retarded with release lasting for several hours, compared with drug loaded microspheres prepared by conventional-spray drying or emulsion methods where drug release was almost instant. The slow release of drug was partly due to the poor wetting ability of the microspheres which floated on the surface of the dissolution medium. The addition of a wetting agent increased the release rate significantly. The coating of the microspheres with gelatin decreased the rate of release of drug in the presence of wetting agents.
开发了改良喷雾干燥方法，特别是一种新型的水包油包水乳液喷雾干燥方法，以制备具有持续药物释放模式的壳聚糖微球。与通过常规喷雾干燥或乳液方法制备的载药微球（药物几乎瞬间释放）相比，通过乳液喷雾干燥方法制备的微球中，模型药物西咪替丁和法莫替丁的释放受到极大延迟，释放持续数小时。药物的缓慢释放部分归因于微球在溶解介质表面漂浮的润湿性差。添加润湿剂显著提高了释放速率。在有润湿剂存在的情况下，用明胶包被微球降低了药物的释放速率。
