医用聚己内酯埋植剂体内降解的研究  

Study on degradation of PCL implant in vivo

作　　者：唐丽娜[1] 宋存先[1] 孙洪范[1] 冷希岗[1] 梅林[1] 

机构地区：[1]中国医学科学院,中国协和医科大学生物医学工程研究所,天津300192

出　　处：《生物医学工程与临床》2007年第4期263-267,F0003,共6页Biomedical Engineering and Clinical Medicine

基　　金：国家高科技研究发展计划(863计划)(2004AA2Z3060)

摘　　要：目的对医用聚己内酯埋植剂材料合成及体内降解进行研究,了解埋植剂材料的性能。方法Pluronic F68经乙酰封端处理后与己内酯单体(CL)混合,加入催化剂于N2保护的聚合釜中,在140℃～170℃条件下聚合48h,用挤出机制成管材。研究致孔剂的工艺、微孔的形成。用核磁共振和扫描电镜等方法观察聚己内酯埋植剂材料的结构。用氚标记的低相对分子量的聚己内酯胶囊植入大鼠皮下,测定其体内降解、吸收和排泄。结果含有F68的医用聚己内酯埋植剂材料(PCL/F68)在亲水介质中F68很快溶出,可形成多微孔结构。该材料起始相对分子量为66000时,在体内可完整存在2年,2年后降解为低相对分子量碎片,可被机体吸收、排泄,不在体内积蓄。结论聚己内酯/F68埋植剂材料在体内可降解并主要通过粪便排出体外,不在体内积蓄,脏器中放射性极少。Objective To study the degradation of poly caprolactone （PCL）-based implant in vivo for study the characteristics of the implant material. Methods PCL/F68 was synthesized by bulk polymerization. The terminal hydroxyl groups in pluronic F68 molecules were acetylized thus it became inactive and would not join in the polymerization reaction of caprolactone. The acetyl-capped F68 was dissolved in caprolactone monomer before polymerization so that F68 was incorporated in PCL matrixes as a molecular dispersion instead of forming a copolymer. The polymerization was carried out at 140 ℃ under high vacuum for 24 h with 0.04 % stannous octoate as catalyst. The mechanism of the microporous formation was studied. The structure of PCL-based implant was studied by scanning electron microscopy and nuclear magnetic resonance methods. Tritium-labeled PCL （Mw 3000） was subcutaneously implanted in rats to study its absorption and excretion. Results Pluronic F68 dispersed in the PCL matrixs could be rapidly dissolved in aqueous medium to form microporous structure. The PCL capsules with an initial molecular weight of 66 000 remained intact in vivo for 2 years. Afterwards the PCL capsules gradually lost strength and broke into pieces. The material did not cumulate in any of the body organs. Coulusion The PCL/F68 capsules do not cumulate in body tissue and could be completely excreted;thus provide a promising material for controlled implant.

关 键 词：聚己内酯 生物降解 缓释体系 埋植剂 

分 类 号：R318.08[医药卫生—生物医学工程]