硝苯地平双层控释片的制备与体外释放

Preparation and in vitro evaluation of nifedipine osmotic pump system

目的:采用渗透泵技术,制备硝苯地平控释片,并进行体外释放研究。方法:采用单因素筛选处方,分别考察含药层高分子聚氧乙烯(PEO)相对分子质量、含药层渗透压活性物质、助推层中高分子PEO相对分子质量、助推层的含量、压力、包衣膜厚度和释药孔孔径等因素对释放度的影响。结果:通过系列研究,结果表明,衣膜的完整性、能否释放药物以及释药速度的快慢主要受含药层中高分子PEO的相对分子质量、渗透压活性物质和助推层中高分子PEO相对分子质量、含药层和助推层体积比及压力、孔径、半透膜等因素的影响。结论:自制的硝苯地平双层渗透泵控释片在体外释药条件下释药稳定,在3～14h内零级特征明显(r=0.9995)、平均释药量约为8%/h、衣膜完整。

OBJECTIVE To investigate the preparation and in vitro evaluation of nifedipine osmotic pump formulations were investigated. METHODS In present study, insoluble nifedipine was as the model drug to prepare the bi-layer osmotic pump tablets with polyethylene oxide （PEO） as the main excJpients of the tablet core. The effects of many factors including formula- tion of drug layer, push layer and membrane, arts of tablet and the conditions of drug release on the release behavior of con- trolled release tablets were investigated by single factor optimization method. RESULTS After comprehensive formulation re- search, the release profile was influenced by PEO molecular weight, volume ratio of drug layer and push layer, hardness, orifice and coating membrane. CONCLUSION The results indicated that drug release profiles of the optimal formulation had the excellent zero-order release character （8%/h release rate） in vitro from 3 to 14 hours （r= 0. 999 5） with intact coating membrane.