Akkineni Ashwini Rahul, Ahlfeld Tilman, Funk Alexander, Waske Anja, Lode Anja, Gelinsky Michael
Centre for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus and Faculty of Medicine of Technische Universität Dresden, 01307 Dresden, Germany.
IFW Dresden, Institute for Complex Materials, P.O. 270116, 01171 Dresden, Germany.
Polymers (Basel). 2016 Apr 26;8(5):170. doi: 10.3390/polym8050170.
In tissue engineering, additive manufacturing (AM) technologies have brought considerable progress as they allow the fabrication of three-dimensional (3D) structures with defined architecture. 3D plotting is a versatile, extrusion-based AM technology suitable for processing a wide range of biomaterials including hydrogels. In this study, composites of highly concentrated alginate and gellan gum were prepared in order to combine the excellent printing properties of alginate with the favorable gelling characteristics of gellan gum. Mixtures of 16.7 wt % alginate and 2 or 3 wt % gellan gum were found applicable for 3D plotting. Characterization of the resulting composite scaffolds revealed an increased stiffness in the wet state (15%⁻20% higher Young's modulus) and significantly lower volume swelling in cell culture medium compared to pure alginate scaffolds (~10% ~23%). Cytocompatibility experiments with human mesenchymal stem cells (hMSC) revealed that cell attachment was improved-the seeding efficiency was ~2.5⁻3.5 times higher on the composites than on pure alginate. Additionally, the composites were shown to support hMSC proliferation and early osteogenic differentiation. In conclusion, print fidelity of highly concentrated alginate-gellan gum composites was comparable to those of pure alginate; after plotting and crosslinking, the scaffolds possessed improved qualities regarding shape fidelity, mechanical strength, and initial cell attachment making them attractive for tissue engineering applications.
在组织工程中，增材制造（AM）技术取得了显著进展，因为它们能够制造具有特定结构的三维（3D）结构。3D打印是一种通用的、基于挤压的增材制造技术，适用于加工包括水凝胶在内的多种生物材料。在本研究中，制备了高浓度海藻酸盐和结冷胶的复合材料，以结合海藻酸盐优异的打印性能和结冷胶良好的凝胶特性。发现16.7 wt%海藻酸盐与2 wt%或3 wt%结冷胶的混合物适用于3D打印。对所得复合支架的表征显示，与纯海藻酸盐支架相比，其在湿态下的刚度增加（杨氏模量高15%⁻20%），在细胞培养基中的体积膨胀显著降低（约10% ~23%）。用人间充质干细胞（hMSC）进行的细胞相容性实验表明，细胞附着得到改善——复合材料上的接种效率比纯海藻酸盐高约2.5⁻3.5倍。此外，该复合材料被证明能够支持hMSC的增殖和早期成骨分化。总之，高浓度海藻酸盐-结冷胶复合材料的打印保真度与纯海藻酸盐相当；在打印和交联后，支架在形状保真度、机械强度和初始细胞附着方面具有更好的品质，使其在组织工程应用中具有吸引力。
