体外条件对不同类型灯盏花素缓控释制剂释放行为的影响

Insoluble breviscapin was chosen as the model drug.Bi-layer osmotic pump technology and gel matrix technology were used to prepare the breviscapin sustained and controlled release preparations.Dissimilarity factors（f1） and similarity factors（f2） were applied as similar judgment index to compare the effects of in vitro conditions on the release behavior of different types of breviscapin sustained and controlled release preparations.The tolerance of in vitro release conditions of bi-layer osmotic pump technology and gel matrix technology were studied.The results showed that in vitro release conditions have a greater impact on the gel matrix sustained release formulations,while have almost no effects on the osmotic pump controlled release formulations.Therefore,osmotic pump controlled release technology is less affected by the drug release environment.And it has a very good application prospect.

多西他赛皮下注射缓释凝胶的制备及其体外释放行为研究

目的以pH/温度双重敏感嵌段共聚物OSM1-PCLA-PEG-PCLA-OSM1为载体,制备多西他赛缓释凝胶,并研究其体外释药行为。方法考察空白凝胶体外溶蚀情况;采用薄膜分散法制备多西他赛缓释凝胶,观察载药共聚物胶束形态,并进行体外释放考察。结果多西他赛缓释凝胶体外释放持续16d,不同共聚物浓度、不同载药量缓释凝胶中多西他赛第16天平均累积释放百分量分别为88.22%,84.06%,81.79%和78.78%,81.79%,87.51%。体外释放模型拟合符合零级释放动力学特征,满足以溶蚀、扩散相结合的释药模式。结论以pH/温度双重敏感嵌段共聚物OSM1-PCLA-PEG-PCLA-OSM1为载体制备的多西他赛缓释凝胶具有良好的缓释效果。

磺胺甲嘧啶及其酰化物与低聚物的pH敏感性研究

目的:考察磺胺甲嘧啶(SM1)、磺胺甲嘧啶酰化物(SM1M)和磺胺甲嘧啶低聚物(OSM1)的pH敏感性,为将其设计成pH敏感单体提供依据。方法:制备SM1、SM1M和OSM1的NaOH溶液,采用电位滴定法,用0.01 mol/L的盐酸溶液进行滴定,测定SM1、SM1M和OSM1的解离常数(pKa)。采用紫外分光光度法,在256、270、268 nm波长处测定SM1、SM1M、OSM1在6.0、6.5、7.0、7.2、7.4、7.5、8.0 pH下的溶解度。结果:SM1、SM1M、OSM1的pKa分别为6.21、6.64、7.21;随着pH的增加,SM1、SM1M、OSM1的溶解度均有增大的趋势,但对pH变化的敏感程度表现不同。结论:SM1、SM1M和OSM1具有不同程度的pH敏感性,将其作为pH敏感单体具有一定的应用价值。