热处理改善聚乳酸纤维膜力学及细胞阻隔性能  

Improved Mechanical Strength and Cell Occlusivity of Electrospun L-polylactic Acid Aligned Nanofibrous Membranes by Post Heat Treatment

作　　者：张慎[1] 蔡晴[1] 张静[1] 梅芳[1] 杨小平[1] 

机构地区：[1]北京化工大学碳纤维及功能高分子材料教育部重点实验室,北京100029

出　　处：《生物医学工程学杂志》2011年第5期951-956,共6页Journal of Biomedical Engineering

基　　金：国家自然科学基金资助项目(50873012);国际科技合作计划项目资助(2007DFA30690);国家高技术研究发展863计划项目资助(2007AA03Z328766);新世纪优秀人才支持计划项目资助

摘　　要：静电纺丝(ES)纳米纤维材料具有与天然细胞外基质相似的形态结构,能很好地支持细胞黏附与生长,是一种理想的组织工程支架,但其力学性能较差,易变形开裂,不能满足引导组织再生(GTR)对于膜机械强度的要求。本文将高速卷绕收集的左旋聚乳酸平行纳米纤维膜(PLLA-ANM)在热空气中进行牵伸及退火处理,以提高膜的抗拉性能和细胞阻隔功能。力学结果表明,在100℃下沿纤维排列方向上牵伸2倍、热定型10 min的膜抗拉性能最好,其抗拉强度(σm)和模量(Et)分别达到了103 MPa和1.83 GPa。体外细胞培养结果显示,牙周膜细胞在热处理后的膜表面黏附和生长状况良好,细胞均沿纤维排列的方向铺展成长梭形,但其增殖速率与无纺纤维膜上的情况相比有所减小。由于热处理后的膜更加致密,细胞仅聚集在膜的表面生长,膜的细胞阻隔性能因此得以明显改善。Electrospun nanofibrous materials are considered as ideal scaffolds for tissue engineering because their fibrous structure is quite similar to the morphology of natural extracellular matrix, and they can offer biomimetie microenvironment for cell growth. However, the highly porous scaffolds are too weak to meet the mechanical require ment of guided tissue regeneration（GTR）. In the present investigation, electrospun L-polylactic acid （PLLA） nano- fibrous membranes were collected with high speed rolling method, and then hot stretched and annealed to improve the tensile strength and cell occlusivity. The membrane with the maximum tensile strength （strength 103MPa and modulus 1.83GPa） was obtained by hot-stretching for twice at 100＂C and further annealed for 10min at the same temperature. Cytotoxicity test showed that the heat treated membrane supported well the attachment and growth of human periodontal ligament cells, but inhibited the cell proliferation. The cell occlusivity of the membrane was also significantly improved as the porosity decreased after heat treatment. It could be used as the enhancement interlayer of barrier materials for GTR.

关 键 词：静电纺丝 聚乳酸 纳米纤维 引导组织再生 热牵伸 

分 类 号：R318.01[医药卫生—生物医学工程]