医用级可降解聚乳酸材料的合成与应用  

Synthesis and Application of Medical Grade Polylactic Acid Materials

作　　者：尹洪喜 高亚萍[1,2] 薛贯鲁 李舒[3] 周灿旭 YIN Hongxi;GAO Yaping;XUE Guanlu;LI Shu;ZHOU Canxu(Jining Technician College,Jining 272000,China;Jining Key Laboratory of Metallographic Analysis,Jining 272000,China;Qingyan Advanced Manufacturing Industry Research Institute(shanxian)Co.,Ltd.,Heze 274300,China;Material college,Tsinghua University,Beijing 100084,China)

机构地区：[1]济宁市技师学院,山东济宁272000 [2]济宁市金相分析重点实验室,山东济宁272000 [3]清研先进制造产业研究院(单县)有限公司,山东菏泽274300 [4]清华大学材料学院,北京100084

出　　处：《合成化学》2024年第10期860-865,共6页Chinese Journal of Synthetic Chemistry

基　　金：济宁市产业升级类重点研发计划项目(2021ZDZP039)。

摘　　要：聚乳酸(PLA)因具有良好的生物相容性和生物降解性,广泛应用于包装材料、医用缝合线、组织工程支架和药物控制释放体系等医学领域。丙交酯开环聚合是制备聚乳酸的理想之选,其催化体系目前以金属催化剂为主,但金属离子在聚合物中的痕量残留和细胞毒性限制了聚乳酸在生物医学的应用。本文利用改进两步法合成了分子量可控的医用级可降解聚乳酸材料,采用^(1)H NMR、IR、GPC和HPLC确证了其结构,研究了十二醇加入量、聚合时间对合成聚乳酸分子量和性能的影响规律。利用3D打印技术设计成型了PLA骨钉,并研究了其降解行为、溶血率和细胞毒性。结果表明:聚合温度为130℃,反应时间为24 h,加入辛酸亚锡0.05%(质量分数,下同)、十二醇0.03%时,聚乳酸重均分子量在35万以上,纯度可达99.0%以上,分布指数为2.031;骨钉在PBS缓冲液中降解10周(w),残余量为23.4%,降解性能良好;溶血率小于5%,100%试验液的细胞存活率为75%,大于国标参考值70%,未发现潜在细胞毒性。Polylactic acid(PLA)is widely used in the medical field,including as packaging materials,medical sutures,tissue engineering scaffolds and drug-controlled release systems,due to its excellent biocompatibility and biodegradability.The ring-opening polymerization of lactide is an ideal method for the synthesis of PLA,with metal catalysts being the predominant catalytic system.However,the trace amounts of metal ions remaining in the polymer and their cytotoxicity limit the biomedical applications of PLA.In this study,a two-step improved method was employed to synthesize medical-grade degradable PLA with controlled molecular weight.The structure of the PLA material was characterized by ^(1)H NMR,IR,GPC and HPLC.The influence of the amount of dodecanol and the polymerization time on the molecular weight and properties of the synthesized PLA was investigated.PLA bone nails were designed and fabricated using 3D printing technology,and their degradation behavior,hemolysis rate,and cytotoxicity were studied.The results showed that at a polymerization temperature of 130℃,a reaction time of 24 hours,the addition of 0.05%(mass fraction,same below)tin octoate,and 0.03% mass ratio dodecanol,the number-average molecular weight of PLA was over 350,000,with a purity exceeding 99.0%and dispersity index was 2.031.The nails degraded by ten weeks in PBS buffer solution,with a residue of 23.4%,demonstrating good degradation performance.The hemolysis rate was less than 5%,and no cytotoxicity was observed because the cell survival rate of 100% test solution was 75%,which was higher than the reference value of 70%.

关 键 词：医用级聚乳酸 骨钉 降解行为 分子量 细胞毒性 

分 类 号：O632.52[理学—高分子化学]