Han Fengxuan, Yang Xiaoling, Zhao Jin, Zhao Yunhui, Yuan Xiaoyan
School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin, 300072, People's Republic of China.
J Mater Sci Mater Med. 2015 Apr;26(4):160. doi: 10.1007/s10856-015-5489-0. Epub 2015 Mar 19.
A layered gelatin-chitosan hydrogel with graded composition was prepared via photocrosslinking to simulate the polysaccharide/collagen composition of the natural tissue and mimic the multi-layered gradient structure of the cartilage-bone interface tissue. Firstly, gelatin and carboxymethyl chitosan were reacted with glycidyl methacrylate (GMA) to obtain methacrylated gelatin (Gtn-GMA) and carboxymethyl chitosan (CS-GMA). Then, the mixed solutions of Gtn-GMA in different methacrylation degrees with CS-GMA were prepared to form the superficial, transitional and deep layers of the hydrogel, respectively under the irradiation of ultraviolet light, while polyhedral oligomeric silsesquioxane was introduced in the deep layer to improve the mechanical properties. Results suggested that the pore sizes of the superficial, transitional and deep layers of the layered hydrogel were 115 ± 30, 94 ± 34, 51 ± 12 μm, respectively and their porosities were all higher than 80 %. The compressive strengths of them were 165 ± 54, 565 ± 50 and 993 ± 108 kPa, respectively and the strain of the gradient hydrogel decreased along the thickness direction, similar to the natural tissue. The in vitro cytotoxicity results showed that the hydrogel had good cytocompatibility and the in vivo repair results of osteochondral defect demonstrated remarkable recovery by using the gradient gelatin-chitosan hydrogel, especially when the hydrogel loading transforming growth factor-β1. Therefore, it was suggested that the prepared layered gelatin-chitosan hydrogel in this study could be potentially used to promote cartilage-bone interface tissue repair.
通过光交联制备了一种具有梯度组成的层状明胶 - 壳聚糖水凝胶，以模拟天然组织的多糖/胶原蛋白组成，并模仿软骨 - 骨界面组织的多层梯度结构。首先，使明胶和羧甲基壳聚糖与甲基丙烯酸缩水甘油酯（GMA）反应，得到甲基丙烯酸化明胶（Gtn - GMA）和羧甲基壳聚糖（CS - GMA）。然后，制备不同甲基丙烯酸化程度的Gtn - GMA与CS - GMA的混合溶液，分别在紫外光照射下形成水凝胶的表层、过渡层和深层，同时在深层引入多面体低聚倍半硅氧烷以改善机械性能。结果表明，层状水凝胶表层、过渡层和深层的孔径分别为115±30、94±34、51±12μm，孔隙率均高于80％。它们的抗压强度分别为165±54、565±50和993±108kPa，梯度水凝胶的应变沿厚度方向降低，类似于天然组织。体外细胞毒性结果表明，该水凝胶具有良好的细胞相容性，软骨 - 骨缺损的体内修复结果表明，使用梯度明胶 - 壳聚糖水凝胶有显著的恢复效果，尤其是当水凝胶负载转化生长因子 - β1时。因此，本研究制备的层状明胶 - 壳聚糖水凝胶有望用于促进软骨 - 骨界面组织修复。
