基于立构复合晶的聚乳酸微孔膜表面微纳结构与疏水性调控及血液相容性研究

Fabrication of the super-hydrophobic surface can improve the biocompatibility and clinical application of poly(lactic acid) (PLA). However, PLA has abundant hydrophilic functional groups and high surface tension, and then it is difficult to build super-hydrophobic surface for PLA. Based on the formation of stereocomplex crystals through blending of poly(L-lactic acid) and poly(D-lactic acid) and its following promoting gel forming properties during the non-solvent induced phase transformation process, super-hydrophobic PLA porous membranes with micro/nano structure are prepared using PLA with different optical activity as the materials. The effect of crystal structure on the thermodynamic and kinetic properties during the phase separation is also explored to revealing the evolution process and mechanism of microstructure. The micro/nano microstructure and wetting properties of resulted PLA membranes would be manipulated by introducing various PLA topological chain structures and fluorine polymers. The relationships of multiscale microstructures for PLA membrane surface with the attached behaviors of common proteins and the cell biological behaviors are investigated. The effect of multiscale microstructures on the in vitro antithrombogenicity and hemolytic properties under static and dynamic loads are studied. As a result, a suitable in vitro blood compatibility evaluation method for rough surface materials is established. This work is expected to provide a new idea for expanding the application of PLA in the field of biological medicine and to provide the guidance for accurately building multiscale micro/nano structures of biological materials.

构建超疏水聚乳酸膜表面可提高其生物相容性和医学临床使用价值，然而聚乳酸具有较多的亲水官能团和较大的表面张力，导致疏水性表面制备困难。基于左旋和右旋聚乳酸共混形成立构复合晶及其在非溶剂诱导相转化过程中促进凝胶形成的特性，本项目以不同旋光性的聚乳酸作为膜材料制备出具有超疏水微纳结构表面的聚乳酸微孔膜，探明立构复合晶对制膜过程中热力学和动力学性质的影响，揭示膜表面微纳结构的演化过程及机理，通过引入分子链拓扑结构聚乳酸和含氟烯烃聚合物实现膜表面微纳结构与润湿性能的灵活调控。阐明膜表面特性与蛋白质贴附行为以及细胞生物学行为之间的关系，解析静态和动态下膜表面特性对抗凝血和溶血性能的影响规律，建立一套适用于粗糙材料表面体外血液相容性评估的方法。预期研究成果为拓展聚乳酸在生物医疗领域的应用提供新思路新方法，为正确构建具有多尺度微纳结构的超疏水生物材料表面提供方向指导。

构建超疏水聚乳酸膜表面可提高其生物相容性和医学临床使用价值，然而聚乳酸具有较多的亲水官能团和较大的表面张力，导致疏水性表面制备困难。基于左旋和右旋聚乳酸共混形成立构复合晶及其在非溶剂诱导相转化过程中促进凝胶形成的特性，本项目以不同旋光性的聚乳酸作为膜材料制备出具有超疏水特性的多尺度微纳结构聚乳酸微孔膜，探明立构复合晶对制膜过程中热力学和动力学性质的影响，揭示膜表面微纳结构的演化过程及机理。通过引通过机械剥离微孔膜表层实现膜表面微纳结构与润湿性能的灵活调控，获得一种制备具有超疏水聚乳酸微孔膜的新方法。阐明膜表面疏水特性对抗凝血和溶血性能的影响规律，建立适用于超疏水表面体外血液相容性评估的方法。预期研究成果不仅为拓展聚乳酸在生物医疗领域的应用提供新思路新方法，同时为正确构建具有多尺度微纳结构的超疏水生物材料表面提供方向指导。