Division of Biomedical Engineering, College of Engineering, University of Saskatchewan, Saskatoon, SK., Canada.
Biofabrication. 2016 Jun 22;8(2):025020. doi: 10.1088/1758-5090/8/2/025020.
Three-dimensional (3D)-printed poly(ε)-caprolactone (PCL)-based scaffolds are increasingly being explored for cartilage tissue engineering (CTE) applications. However, ensuring that the mechanical properties of these PCL-based constructs are comparable to that of articular cartilage that they are meant to regenerate is an area that has been under-explored. This paper presents the effects of PCL's molecular weight (MW) and scaffold's pore geometric configurations; strand size (SZ), strand spacing (SS), and strand orientation (SO), on mechanical properties of 3D-printed PCL scaffolds. The results illustrate that MW has significant effect on compressive moduli and yield strength of 3D-printed PCL scaffolds. Specifically, PCL with MW of 45 K was a more feasible choice for fabrication of visco-elastic, flexible and load-bearing PCL scaffolds. Furthermore, pore geometric configurations; SZ, SS, and SO, all significantly affect on tensile moduli of scaffolds. However, only SZ and SS have statistically significant effects on compressive moduli and porosity of these scaffolds. That said, inverse linear relationship was observed between porosity and mechanical properties of 3D-printed PCL scaffolds in Pearson's correlation test. Altogether, this study illustrates that modulating MW of PCL and pore geometrical configurations of the scaffolds enabled design and fabrication of PCL scaffolds with mechanical and biomimetic properties that better mimic mechanical behaviour of human articular cartilage. Thus, the modulated PCL scaffold proposed in this study is a framework that offers great potentials for CTE applications.
三维（3D）打印的聚己内酯（PCL）基支架越来越多地被探索用于软骨组织工程（CTE）应用。然而，确保这些基于 PCL 的构建体的机械性能与它们旨在再生的关节软骨相当，是一个尚未得到充分探索的领域。本文介绍了 PCL 的分子量（MW）和支架的孔几何构型；股线大小（SZ）、股线间距（SS）和股线方向（SO）对 3D 打印 PCL 支架机械性能的影响。结果表明，MW 对 3D 打印 PCL 支架的压缩模量和屈服强度有显著影响。具体来说，MW 为 45 K 的 PCL 更适合制造粘弹性、柔性和承重的 PCL 支架。此外，孔几何构型；SZ、SS 和 SO 都显著影响支架的拉伸模量。然而，只有 SZ 和 SS 对这些支架的压缩模量和孔隙率有统计学意义的影响。也就是说，在 Pearson 相关性测试中，观察到 3D 打印 PCL 支架的孔隙率和机械性能之间呈负线性关系。总的来说，这项研究表明，调节 PCL 的 MW 和支架的孔几何构型可以设计和制造具有更好模拟人关节软骨机械行为的机械和仿生特性的 PCL 支架。因此，本研究中提出的调制 PCL 支架为 CTE 应用提供了巨大的潜力。
