Buj-Corral Irene, Sanz-Fraile Héctor, Ulldemolins Anna, Tejo-Otero Aitor, Domínguez-Fernández Alejandro, Almendros Isaac, Otero Jorge
Department of Mechanical Engineering, School of Engineering of Barcelona (ETSEIB), Universitat Politècnica de Catalunya, Av. Diagonal 647, 08028 Barcelona, Spain.
Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain.
Polymers (Basel). 2022 Jul 5;14(13):2754. doi: 10.3390/polym14132754.
Three-dimensional printing is revolutionizing the development of scaffolds due to their rapid-prototyping characteristics. One of the most used techniques is fused filament fabrication (FFF), which is fast and compatible with a wide range of polymers, such as PolyLactic Acid (PLA). Mechanical properties of the 3D printed polymeric scaffolds are often weak for certain applications. A potential solution is the development of composite materials. In the present work, metal-PLA composites have been tested as a material for 3D printing scaffolds. Three different materials were tested: copper-filled PLA, bronze-filled PLA, and steel-filled PLA. Disk-shaped samples were printed with linear infill patterns and line spacing of 0.6, 0.7, and 0.8 mm, respectively. The porosity of the samples was measured from cross-sectional images. Biocompatibility was assessed by culturing Human Bone Marrow-Derived Mesenchymal Stromal on the surface of the printed scaffolds. The results showed that, for identical line spacing value, the highest porosity corresponded to bronze-filled material and the lowest one to steel-filled material. Steel-filled PLA polymers showed good cytocompatibility without the need to coat the material with biomolecules. Moreover, human bone marrow-derived mesenchymal stromal cells differentiated towards osteoblasts when cultured on top of the developed scaffolds. Therefore, it can be concluded that steel-filled PLA bioprinted parts are valid scaffolds for bone tissue engineering.
三维打印因其快速成型特性正在彻底改变支架的发展。最常用的技术之一是熔融长丝制造（FFF），它速度快且与多种聚合物兼容，如聚乳酸（PLA）。对于某些应用而言，3D打印聚合物支架的机械性能往往较弱。一个潜在的解决方案是开发复合材料。在本研究中，金属-PLA复合材料已被测试作为3D打印支架的材料。测试了三种不同的材料：铜填充PLA、青铜填充PLA和钢填充PLA。分别以0.6、0.7和0.8毫米的线性填充图案和行距打印盘形样品。从横截面图像测量样品的孔隙率。通过在打印支架表面培养人骨髓间充质基质来评估生物相容性。结果表明，对于相同的行距值，孔隙率最高的对应于青铜填充材料，最低的对应于钢填充材料。钢填充PLA聚合物显示出良好的细胞相容性，无需用生物分子包被材料。此外，当在开发的支架上培养时，人骨髓间充质基质细胞向成骨细胞分化。因此，可以得出结论，钢填充PLA生物打印部件是骨组织工程的有效支架。
