Physically cross-linked collagen hydrogel is a desirable scaffold for tissue engineering applications especially where 3D cell encapsulation is considered. To overcome its shortcomings such as weak mechanical properties and also provide additional benefits, nanofiller reinforcement could be applied. This study was conducted to compare physical properties and cellular performance of physically cross-linked collagen hydrogel reinforced with cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs). Addition of both nanofillers drastically changed the hydrogel properties depending on the type and concentration. As a general trend, both CNCs and CNFs resulted in reduction in gelation time, enhancement in compressive strength, increase in swelling ratio, decrease in weight loss and improvement of injectability. The highest impact for CNCs was achieved when 5 % was applied, while the maximum impact for CNFs was observed for 3 % content (related to the collagen solid weight). By comparing two types of nanocellulose, CNCs showed higher impact on all properties. In-vitro cell compatibility with fibroblasts showed that CNFs did not adversely affected the viability and morphology of the cells while the CNCs improved cell viability and developed more elongated cell morphology.

物理交联的胶原水凝胶是组织工程应用的理想支架，尤其是在考虑 3D 细胞封装的情况下。为了克服其弱机械性能等缺点并提供额外的好处，可以应用纳米填料增强。本研究旨在比较用纤维素纳米晶体 (CNC) 和纤维素纳米原纤维 (CNF) 增强的物理交联胶原水凝胶的物理特性和细胞性能。两种纳米填料的加入极大地改变了水凝胶的性质，具体取决于类型和浓度。作为总体趋势，CNCs 和 CNFs 都导致凝胶时间缩短、抗压强度提高、溶胀率增加、重量损失减少和可注射性提高。当使用 5% 时，CNCs 的影响最大，而在 3% 的含量（与胶原蛋白固体重量相关）时，CNFs 的影响最大。通过比较两种类型的纳米纤维素，CNC 显示出对所有性能的更高影响。体外细胞与成纤维细胞的相容性表明，CNFs 不会对细胞的活力和形态产生不利影响，而 CNCs 提高了细胞活力并形成了更细长的细胞形态。