Li Yihong, Feng Yanjun, Zhao Zhixin, Liu Lei, Li Zhengqiu, Li Jiafeng
School of Material Science and Engineering, Xihua University, Chengdu 610039, China.
CCTEG Coal Mining Research Institute, Beijing, China; State Key Laboratory of Coal Mining and Clean Utilization, Beijing, China.
Int J Biol Macromol. 2025 Jun;311(Pt 2):143918. doi: 10.1016/j.ijbiomac.2025.143918. Epub 2025 May 3.
Poly(-lactic) acid (PLLA) was limited in the application of bone repair materials due to its brittleness, poor melt strength and poor cellular affinity. In this work, single epoxy-terminated polydimethylsiloxane (e-PDMS) was used to extend the molecular chain of PLLA and improve the melt strength of PLLA. Subsequently, a uniform two-dimensional(2D) oriented microporous biomimetic structure was constructed by combining the biaxial orientation technology with the supercritical carbon dioxide (SC-CO) foaming technology, which greatly improved the strength and toughness of PLLA (from 54.9 MPa,7.3 % to 133.6 MPa,72.6 %). This 2D oriented microporous PLLA was also more conducive to the expression of anti-inflammatory factors and pro-inflammatory factors simultaneously in mouse bone marrow macrophages (iBMDM), which had an effect on regulating inflammation. At the same time, this structure was also helpful to the adhesion and growth of mouse embryonic fibroblasts (NIH-3 T3), and can stimulate the activity of mouse embryonic osteoblast precursor cells (MC-3 T3-E1), showing good biocompatibility.
聚乳酸（PLLA）因其脆性、熔体强度差和细胞亲和力低，在骨修复材料的应用中受到限制。在这项工作中，使用单端环氧基聚二甲基硅氧烷（e-PDMS）来延长PLLA的分子链并提高其熔体强度。随后，通过将双轴取向技术与超临界二氧化碳（SC-CO₂）发泡技术相结合，构建了均匀的二维（2D）取向微孔仿生结构，这大大提高了PLLA的强度和韧性（从54.9MPa、7.3%提高到133.6MPa、72.6%）。这种二维取向微孔PLLA在小鼠骨髓巨噬细胞（iBMDM）中也更有利于同时表达抗炎因子和促炎因子，对调节炎症有作用。同时，这种结构也有助于小鼠胚胎成纤维细胞（NIH-3T3）的黏附与生长，并能刺激小鼠胚胎成骨前体细胞（MC-3T3-E1）的活性，表现出良好的生物相容性。
