Štiglic Andreja Dobaj, Gürer Fazilet, Lackner Florian, Bračič Doris, Winter Armin, Gradišnik Lidija, Makuc Damjan, Kargl Rupert, Duarte Isabel, Plavec Janez, Maver Uros, Beaumont Marco, Kleinschek Karin Stana, Mohan Tamilselvan
University of Maribor, Faculty of Mechanical Engineering, Laboratory for Characterization and Processing of Polymers, Smetanova Ulica 17, 2000 Maribor, Slovenia.
Graz University of Technology, Institute for Chemistry and Technology of Biobased System (IBioSys), Stremayrgasse 9, 8010 Graz, Austria.
iScience. 2022 Apr 16;25(5):104263. doi: 10.1016/j.isci.2022.104263. eCollection 2022 May 20.
Herein, we fabricated chemically cross-linked polysaccharide-based three-dimensional (3D) porous scaffolds using an ink composed of nanofibrillated cellulose, carboxymethyl cellulose, and citric acid (CA), featuring strong shear thinning behavior and adequate printability. Scaffolds were produced by combining direct-ink-writing 3D printing, freeze-drying, and dehydrothermal heat-assisted cross-linking techniques. The last step induces a reaction of CA. Degree of cross-linking was controlled by varying the CA concentration (2.5-10.0 wt.%) to tune the structure, swelling, degradation, and surface properties (pores: 100-450 μm, porosity: 86%) of the scaffolds in the dry and hydrated states. Compressive strength, elastic modulus, and shape recovery of the cross-linked scaffolds increased significantly with increasing cross-linker concentration. Cross-linked scaffolds promoted clustered cell adhesion and showed no cytotoxic effects as determined by the viability assay and live/dead staining with human osteoblast cells. The proposed method can be extended to all polysaccharide-based materials to develop cell-friendly scaffolds suitable for tissue engineering applications.
在此，我们使用由纳米原纤化纤维素、羧甲基纤维素和柠檬酸（CA）组成的墨水制备了化学交联的基于多糖的三维（3D）多孔支架，该墨水具有很强的剪切变稀行为和足够的可打印性。通过结合直接墨水书写3D打印、冷冻干燥和脱氢热辅助交联技术来制备支架。最后一步引发CA的反应。通过改变CA浓度（2.5 - 10.0 wt.%）来控制交联度，以调节干燥和水合状态下支架的结构、膨胀、降解和表面性质（孔径：100 - 450μm，孔隙率：86%）。交联支架的抗压强度、弹性模量和形状恢复随着交联剂浓度的增加而显著提高。交联支架促进了细胞聚集粘附，并且通过人成骨细胞的活力测定和活/死染色确定没有细胞毒性作用。所提出的方法可以扩展到所有基于多糖的材料，以开发适用于组织工程应用的细胞友好型支架。
