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但几乎没有柔性植入物而被广泛用作刚性生物医学设备。在此，我们提出一个灵活的聚（丙交酯联合使用快速-glycolide）（PLGA）支架原位基于溶剂交换沉积建模（SEDM）的相分离的成膜系统，与传统的3D打印熔融沉积建模（FDM）不同。FDM印刷产品具有刚性，其杨氏模量约为SEDM印刷样品的2.6倍。此外，固化墨水的厚度在SEDM印刷过程中不会收缩，其表面具有纳米/微孔，有利于蛋白质固定和细胞粘附。然后结合SEDM和静电纺丝技术构建了具有纳米/微观结构的柔性双层支架，用于皮肤替代，其中SEDM印刷的样品充当细胞和组织向内生长的子层，致密堆积的电纺纳米纤维充当上层改进子层的抗拉强度提高了57。07％并以防止细菌作为物理屏障。最终，通过生物正交方法成功地将双层支架固定的表皮生长因子（EGF）应用于促进大鼠全层伤口愈合。