A novel sandwich-like composite 3D model integrated with deposited gelatin film and printed polycaprolactone (PCL)/polyvinyl pyrrolidone (PVP) scaffold is proposed for 3D cartilage cell culture. The 3D model includes three layers, top scaffold, middle gelatin film, and basal slide. The printed scaffold layer mimicking extracellular matrix is employed to provide 3D regeneration architecture; gelatin film layer is used for fixing printed scaffold and catching falling cells. Electrospray and electrohydrodynamic jet printing technologies are combined to construct sandwich-like composite 3D model. The blended constructing processes are investigated thoroughly both theoretically and experimentally. The retained charges on the gelatin film are influenced the electric field distribution and jet behaviors during printing. The characteristics of gelatin film and composite scaffold are studied. The thickness, surface roughness, and planeness of one layer of deposited gelatin film are 400 nm, 22 nm, and 2.27 µm; the size of printed PCL/PVP composite fiber is 10 µm. The fabricated sandwich-like composite 3D model is proved to facilitate adhesion and ingrowth of cartilage cells.

中文翻译：

---

三明治样明胶/聚己内酯/聚乙烯吡咯烷酮 3D 模型，显着改善软骨细胞粘附和再生

提出了一种新型三明治状复合 3D 模型，该模型与沉积的明胶膜和印刷的聚己内酯 (PCL)/聚乙烯吡咯烷酮 (PVP) 支架相结合，用于 3D 软骨细胞培养。3D模型包括三层，顶部支架、中间明胶膜和基底玻片。采用模拟细胞外基质的打印支架层提供 3D 再生结构；明胶膜层用于固定印刷支架和捕捉掉落的细胞。将电喷雾和电流体动力喷射打印技术相结合，构建出类似三明治的复合 3D 模型。混合构造过程在理论和实验上都得到了彻底的研究。明胶薄膜上的保留电荷会影响打印过程中的电场分布和喷射行为。研究了明胶膜和复合支架的特性。一层沉积明胶膜的厚度、表面粗糙度和平面度分别为400 nm、22 nm和2.27 μm；印刷PCL/PVP复合纤维的尺寸为10 µm。制造的三明治状复合 3D 模型被证明有助于软骨细胞的粘附和向内生长。