左旋聚乳酸-甲壳素共混材料体外降解的形态学观察

Morphological Observation on the Degradation of Poly-L-lactic Acid/Chitin Composite in vitro

目的从形态学的角度观察加入甲壳素后,左旋聚乳酸-甲壳素共混材料降解方式的变化。方法将左旋聚乳酸-甲壳素共混材料制成条板状,以单纯聚乳酸条板为对照,材料浸泡于磷酸缓冲液中,分别于第4、8、12、24、32、44周随机各取3条行大体形态和扫描电镜下截面的微观形态观察,评价甲壳素在体外条件下对左旋聚乳酸降解方式的影响。结果单纯聚乳酸条板表现为简单水解的降解过程,而左旋聚乳酸-甲壳素共混材料除此之外,还见有自条板上逐渐分离出颗粒状材料。结论甲壳素的加入改变了左旋聚乳酸简单水解的降解方式。

Objective To observe the effect of chitin （CHI） on the degradation of poly-L-latic acid （PLLA） in vitro morphologically. Methods Eighteen rods made of PLLA and CHI composite, and eighteen rods made of PLLA as control, were incubated in thirty-six tubes containing PBS （pH 7.4） respectively for degradation. Three rods of each material were selected randomly for observation of macroscopic and microscopic changes at weeks 4, 8, 12, 24, 32 and 44. Results In addition to simple hydrolysis like PLLA degradation, the PLLA-CHI rods appeared pores and channels dilated and extended to the margin of the material. Conclusion The character of the degradation of PLLA was changed by the addition of CHI.