摘要
通过左旋丙交酯开环聚合法制取分子量 42万的聚左旋丙交酯 (PLLA)用于制备可降解骨折内固定物。由PLLA原料经不同的成型工艺方法制备了三种棒状骨折内固定物试样。A试样 :将PLLA块状原料直接切削加工成棒状物 ;B试样 :将A试样由乙酸乙酯进行抽提 ;C试样 :将PLLA块状原料粉碎抽提后进行熔融挤出和热拉伸。三种试样在 37℃生理盐水缓冲液中降解 2 80天。考察了试样的分子量、弯曲性能、重量及缓冲液中乳酸浓度等随时间的变化规律。结果表明 :不同的成型工艺 ,PLLA骨折内固定物的降解有很大差异 ,C试样的加工成型方法最为理想。因此我们认为 :用PLLA材料选定合理的成型工艺方法可以制取满足临床应用要求的骨折内固定物。
Poly (L-lactide) (PLLA) was synthesized by ring-opening polymerization from l-lactide with molecular weight of 42×104, Three types of PLLA samples that is used in internal fixation of bone fractions were prepared in different shaping processing methods. Sample A was a PLLA rod, which was cut straightly from synthesized polymer. Sample B was the rod after extraction with ethyl acetate. Sample C was the rods prepared by melt and extrusion of PLLA powder extracted with ethyl acetate. Three types of samples were degraded in phosphate buffer with pH 7.4 at 37℃ for 280 days. It was observed that the molecular weight, bending stress and the nature weight of the three samples and lactic acid content in buffer were changed with degradation times. The results show that there were differences in degradation of the three types of PLLA samples. It is the best method that shaping processing method of sample C. It′s available to obtain internal fixation material of bone fracture by suitable shaping processing to meet clinical demands.
出处
《中国生物医学工程学报》
CAS
CSCD
北大核心
2001年第4期321-325,共5页
Chinese Journal of Biomedical Engineering
