The Ministry of Education Key Laboratory of Bio-based Material Science & Technology, College of Material Science and Engineering, Northeast Forestry University, Harbin 150040, PR China.
Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China.
Mater Sci Eng C Mater Biol Appl. 2020 Jul;112:110942. doi: 10.1016/j.msec.2020.110942. Epub 2020 Apr 8.
Biodegradable polyesters have been widely used as rigid biomedical apparatus because of high mechanical properties but few flexible implants. Herein, we report a flexible poly(lactide-co-glycolide) (PLGA) scaffold using a rapid in situ formation system based on phase separation by solvent exchange deposition modeling (SEDM), which was different from traditional 3D printing of fused deposition modeling (FDM). The FDM printed product was rigidity, its Young's modulus was approximate 2.6 times higher than that of SEDM printed sample. In addition, the thickness of the solidified ink would not shrink during the SEDM printing process, its surface had nano-/micro pores in favor of protein immobilization and cell adhesion. Then a flexible bilayered scaffold with nano-/microstructure was constructed combing SEDM with electrospinning technology for skin substitute, wherein the SEDM printed sample acted as a sub-layer for cell and tissue ingrowth, the densely packed electrospun nanofibers served as an upper-layer improving the sub-layer's tensile strength by 57.07% and preventing from bacteria as physical barrier. Ultimately, the bilayered scaffold immobilized epidermal growth factor (EGF) by a bioorthogonal approach was successfully applied to facilitate full-thickness wound healing of rats.
可生物降解的聚酯由于具有较高的机械性能而被广泛用作刚性生物医学器械，但很少有柔性植入物。在此，我们报告了一种使用基于溶剂交换沉积建模（SEDM）相分离的快速原位形成系统的柔性聚（丙交酯-共-乙交酯）（PLGA）支架，这与传统的熔融沉积建模（FDM）3D 打印不同。FDM 打印产品是刚性的，其杨氏模量比 SEDM 打印样品高约 2.6 倍。此外，在 SEDM 打印过程中，凝固油墨的厚度不会收缩，其表面具有纳米/微孔，有利于蛋白质固定和细胞附着。然后，通过将 SEDM 与静电纺丝技术相结合，构建了一种具有纳米/微观结构的柔性双层支架，用于皮肤替代物，其中 SEDM 打印样品作为细胞和组织生长的子层，密集排列的静电纺纳米纤维作为上层层，使子层的拉伸强度提高了 57.07%，并起到物理屏障的作用，防止细菌。最终，通过生物正交方法将表皮生长因子（EGF）固定在双层支架上，成功地应用于促进大鼠全层伤口愈合。
