摘要
建立3步释放度实验法考察布地奈德结肠定位片的体外释药行为,并通过模型拟合阐明其释药机制。分别模拟胃、小肠和结肠部位的pH值、肠道菌群、特异性生物酶、蠕动和转运时间等生理参数,设计定位片体外释放度试验,24 h内定时取样,HPLC法测定布地奈德的累积释放度,采用多种数学模型对定位片的释药曲线进行拟合度分析。结果表明,布地奈德结肠定位片在2 h内无药物释放,6 h累积释放度约为5%,24 h累积释放度达77.5%,其体外释药行为符合F irst-order模型。本实验建立的3步释放度实验可作为评价布地奈德结肠定位片结肠靶向性的方法,定位片的释药行为遵从以渗透压作为主要释药动力的微孔型渗透泵的释药机制。
The three-step dissolution experiment was established to investigate the in vitro release of budesonide colon-specific tablet and to elucidate the drug release mechanism by fitting to different mathematical models. The physiological parameters of stomach, small intestine and colon such as pH value, intestinal flora, specific organic enzyme, vermiculation and conveying time were mimicked to plot the in vitro dissolution, separately. Sample were taken at predetermined time intervals in 24 h and the accumulated drug releases were determined by using HPLC method. Drug release curves of the localization tablets were fitted to various mathematical models. It shows that no drug release was found in 2 h. About 5% release was determined after 6 h while 77.5% accumulated release was reached within 24 h. Drug release from the in house formulation fitted well into first-order model. The three-step dissolution method could be used to evaluate the colon-specific characteristics of budesonide colonic localization tablet. The drug release behavior of the localization tablet conforms to the drug release mechanisms of controlled porosity osmotic pump where osmotic pressure is the main driving force for controlled delivery of drugs.
出处
《药学学报》
CAS
CSCD
北大核心
2008年第11期1147-1151,共5页
Acta Pharmaceutica Sinica
基金
辽宁省自然科学基金资助项目(20052059)
关键词
布地奈德
结肠定位片
体外释放度
模型拟合
budesonide
colonic localization tablet
in vitro dissolution
fitted mathematical model
