【摘要】 目的 研究不同调控方法对不锈钢表面混合药物涂层中紫杉醇释放速率的影响,并对药物的释放机制进行了研究。方法 研究了聚乙烯-乙烯醇(EVAL)和紫杉醇混合涂层中药物的存在状态,并通过改变外层涂层的厚度、引入溶胀控制剂(swell-ing control agent,SCA)、Ar气低温等离子体(low temperature plasma,LTP)轰击等方法调控紫杉醇的释放速率。并运用Higuchi,Hixcon Crowell,Ritger-Peppas等方程分析了药物的释放机制。结果 药物在涂层中以无定型、均匀分散在聚合物中;药物的释放速率随外层涂层厚度的增加而降低;与外层引入SCA相比,在内层药物和高分子中添加SCA更能有效地降低药物的释放速率;Ar气LTP轰击涂层外表面后,药物的释放速率明显加快;随着LTP处理时间的延长,药物的释放速率加快;但LTP的功率对药物的释放速率无明显影响。药物从混合药物涂层中的释放为Fick扩散,而从含SCA体系中的释放为非Fick扩散。LTP处理改变了药物的释放规律。结论 不锈钢表面EVAL和紫杉醇混合涂层中药物的释放速率可以通过适当的方法进行调控。更多还原

【Abstract】 OBJECTIVE To evaluate the influence of different controlling methods on the drug release property from EVAL/paclitaxel system and the drug release mechanism. METHODS The EVAL/paclitaxel system on stainless steel surface was prepared by solvent evaporation. The coat system included two layers, the inner coat formulated by drug/EVAL matrix and the outer one formulated by EVAL alone. The drug release rate were modulated by outer coat thickness, swell controlling agent and low temperature plasma treatment. The release mechanism was analyzed by Higuchi, Hixcon Crowell and Ritger-Peppas equations. RESULTS With the increasing of outer coat thickness, the drug release rate was decreased. Compared with the coat system which introduced swelling control agent (SCA) into the outer coat, the system with SCA in the inner coat was more effective to reduce the drug release rate, especially in initial period. Drug release rate was accelerated after the coat was treated by low temperature plasma (LTP) . Furthermore, the longer the treat time, the quicker the drug release rate. The treat power had no noticeable effect on the drug release rate. Drug diffusion from drug/EVAL matrix system was Fick diffusion, while that from the coat with SCA were Non- Fick diffusion. LTP treatment changed the drug release model. CONCLUSION The drug release rate could be modulated by different methods.更多还原