Zheng Wang
Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore.
Int J Pharm. 2009 Jun 5;374(1-2):90-5. doi: 10.1016/j.ijpharm.2009.03.015. Epub 2009 Mar 24.
A water-in-oil-in-oil-in-water (W/O/O/W) method was developed to fabricate double-walled microspheres for controlled delivery of drugs and therapeutic proteins with reduced initial burst and prolonged release. By using this method, drugs and therapeutic proteins can be loaded into microspheres in solution form as those used in medical treatments. Proteins can be loaded in solutions together with excipients, thereby reducing the risk of losing stability in the process of protein drying and dispersing. This also benefits uniform distribution of drugs inside polymer matrix in comparison to the case with solid drug particles. These microspheres were characterized to have double-walled structure, with a cavity in the centre. The hydrophilic drugs were encapsulated in the inner polymer layer, while the non-drug-loaded outer layer served as a rate-limiting barrier. Drug release profiles for 5-fluorouracil showed low initial burst and prolonged release, which is substantiated by degradation studies.
开发了一种水包油包油包水（W/O/O/W）方法来制备用于药物和治疗性蛋白质控释的双壁微球，以减少初始突释并延长释放时间。通过使用这种方法，药物和治疗性蛋白质可以以医疗治疗中使用的溶液形式负载到微球中。蛋白质可以与赋形剂一起加载到溶液中，从而降低蛋白质干燥和分散过程中失去稳定性的风险。与固体药物颗粒的情况相比，这也有利于药物在聚合物基质内的均匀分布。这些微球的特征是具有双壁结构，中心有一个空腔。亲水性药物被包裹在内层聚合物中，而未负载药物的外层作为限速屏障。5-氟尿嘧啶的药物释放曲线显示出低初始突释和延长释放，这通过降解研究得到证实。
