Shandong Provincial Key Laboratory of Biochemical Engineering, College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
Shandong Provincial Key Laboratory of Biochemical Engineering, College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
Int J Biol Macromol. 2022 Jul 31;213:639-650. doi: 10.1016/j.ijbiomac.2022.06.006. Epub 2022 Jun 4.
Chemical cross-linking is an important step to grant satisfying properties to collagen-based materials. However, there are few comparative studies on crossing-linking of collagen-based fibrillar gels which are preferred biomaterials for similar properties to native tissues with different cross-linking agents. In this study, a fibrillar gel was fabricated with tilapia collagen and hyaluronic acid, and cross-linking conditions with EDC/NHS and genipin were discussed. Genipin gave gels much higher equilibrium cross-linking degree than EDC/NHS. ATR-FTIR and XPS showed EDC/NHS offered short-range cross-linking formed by amino and carboxyl groups in fibrils, while genipin induced long-range cross-linking by nucleophilic reaction through attack of amino groups in fibrils on carbon atoms at C-3 as well as ester groups in genipin, besides improved hydrogen bonds. XRD and SEM revealed the structural integrity of gels was strengthened after cross-linking, whereas fibril bundles disaggregated into thin fibrils. Consequently, swelling capacity and anti-degraded property were enhanced significantly, while thermal stability weakened. The fibrillar gels had good biocompatibility, but interestingly the appearance and migration of L929 fibroblasts were influenced by cross-linking degree. These results demonstrated that aquatic collagen-based fibrillar gel cross-linked by genipin had greater potential in biomaterials than EDC/NHS, whereas the cross-linking degree should be controlled.
化学交联是赋予基于胶原蛋白的材料令人满意性能的重要步骤。然而，对于基于胶原蛋白的纤维状凝胶的交联，很少有比较研究，这些凝胶是具有类似天然组织性能的首选生物材料，使用不同的交联剂。在这项研究中，用罗非鱼胶原蛋白和透明质酸制备了纤维状凝胶，并讨论了 EDC/NHS 和京尼平的交联条件。京尼平赋予凝胶的平衡交联度远高于 EDC/NHS。ATR-FTIR 和 XPS 表明，EDC/NHS 提供了通过纤维中氨基和羧基之间的短程交联，而京尼平通过纤维中氨基对碳-3 上的碳原子以及京尼平中的酯基的亲核反应诱导长程交联，此外还改善了氢键。XRD 和 SEM 表明交联后凝胶的结构完整性得到增强，而纤维束解聚成细纤维。因此，溶胀能力和抗降解性能显著提高，而热稳定性减弱。纤维状凝胶具有良好的生物相容性，但有趣的是，L929 成纤维细胞的外观和迁移受到交联度的影响。这些结果表明，与 EDC/NHS 相比，用京尼平交联的水生胶原蛋白基纤维状凝胶在生物材料方面具有更大的潜力，但是交联度应该得到控制。
