Jing Xin, Mi Hao-Yang, Turng Lih-Sheng
The Key Laboratory for Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou 510640, China; Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI 53715, United States.
The Key Laboratory for Polymer Processing Engineering of Ministry of Education, South China University of Technology, Guangzhou 510640, China; Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI 53715, United States.
Mater Sci Eng C Mater Biol Appl. 2017 Mar 1;72:53-61. doi: 10.1016/j.msec.2016.11.049. Epub 2016 Nov 15.
In this work, three-dimensional poly(caprolactone) (PCL) tissue engineering scaffolds were prepared by co-extrusion and gas foaming. Biocompatible hydroxyapatite (HA) and halloysite nanotubes (HNT) were added to the polymer matrix to enhance the mechanical properties and bioactivity of the composite scaffolds. The effects of HA and HNT on the rheological behavior, microstructure, and mechanical properties of the composite scaffolds were systematically compared. It was found that the HNT improved viscosity more significantly than HA, and reduced the pore size of scaffolds, while the mechanical performance of PCL/HNT scaffolds was higher than PCL/HA scaffolds with the same filler content. Human mesenchymal stem cells (hMSCs) were used as the cell model to compare the biological properties of two composite scaffolds. The results demonstrated that cells could survive on all scaffolds, and showed a more flourishing living state on the composite scaffolds. The cell differentiation for 5% HA and 1% HNT scaffolds were significantly higher than other scaffolds, while the differentiation of 5% HNT scaffolds was lower than that of 1% HNT scaffolds mainly because of the reduced pore size and pore interconnectivity. Therefore, this study suggested that, with proper filler content and control of microstructure through processing, HNT could be a suitable substitute for HA for bone tissue engineering to reduce the cost and improve mechanical performance.
在本研究中，通过共挤出和气体发泡制备了三维聚己内酯（PCL）组织工程支架。将生物相容性羟基磷灰石（HA）和埃洛石纳米管（HNT）添加到聚合物基质中，以增强复合支架的力学性能和生物活性。系统地比较了HA和HNT对复合支架流变行为、微观结构和力学性能的影响。结果发现，HNT比HA更显著地提高了粘度，并减小了支架的孔径，而在相同填料含量下，PCL/HNT支架的力学性能高于PCL/HA支架。使用人间充质干细胞（hMSCs）作为细胞模型，比较两种复合支架的生物学特性。结果表明，细胞能够在所有支架上存活，并且在复合支架上呈现出更旺盛的生存状态。5%HA和1%HNT支架的细胞分化明显高于其他支架，而5%HNT支架的分化低于1%HNT支架，主要是因为孔径和孔隙连通性降低。因此，本研究表明，通过适当的填料含量和加工过程中微观结构的控制，HNT可以作为HA的合适替代品用于骨组织工程，以降低成本并提高力学性能。
