Chen Jun, Dong Qiuchen, Ma Xiaoyu, Fan Tai-Hsi, Lei Yu
Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269, USA.
Department of Mechanical Engineering, University of Connecticut, Storrs, CT 06269, USA.
Sci Rep. 2016 Aug 22;6:30804. doi: 10.1038/srep30804.
Self-healing is a capacity observed in most biological systems in which the healing processes are autonomously triggered after the damage. Inspired by this natural behavior, researchers believed that a synthetic material possessing similar self-recovery capability could also be developed. Albeit various intrinsic self-healing systems have been developed over the past few decades, restriction on the biocompatibility due to the required synthetic conditions under extreme pH and with poisonous cross-linker significantly limits their application in biomedical field. In this study, a highly biocompatible nanocomposite protein hydrogel with excellent biomimetic self-healing property is presented. The self-healing protein gel is made by inducing calcium ions into the mixture of heat-induced BSA nano-aggregates and pristine BSA molecules at room temperature and under physiological pH due to the ion-mediated protein-protein association and the bridging effect of divalent Ca(2+) ions. The as-prepared protein hydrogel shows excellent repetitive self-healing properties without using any external stimuli at ambient condition. Such outstanding self-recovery performance was quantitatively evaluated/validated by both dynamic and oscillatory rheological analysis. Moreover, with the presence of calcium ions, the self-healing behavior can be significantly facilitated/enhanced. Finally, the superior biocompatibility demonstrated by in vitro cytotoxicity analysis suggests that it is a promising self-healing material well-suited for biomedical applications.
自我修复是在大多数生物系统中观察到的一种能力，其中修复过程在损伤后自动触发。受这种自然行为的启发，研究人员认为也可以开发出具有类似自我恢复能力的合成材料。尽管在过去几十年中已经开发出各种内在的自我修复系统，但由于在极端pH值下所需的合成条件以及使用有毒交联剂而对生物相容性的限制，严重限制了它们在生物医学领域的应用。在本研究中，提出了一种具有优异仿生自我修复性能的高生物相容性纳米复合蛋白质水凝胶。这种自我修复蛋白质凝胶是通过在室温及生理pH值下，由于离子介导的蛋白质-蛋白质缔合和二价Ca(2+)离子的桥接作用，将钙离子引入热诱导的牛血清白蛋白（BSA）纳米聚集体与原始BSA分子的混合物中制成的。所制备的蛋白质水凝胶在环境条件下无需任何外部刺激即可表现出优异的重复自我修复性能。通过动态和振荡流变学分析对这种出色的自我恢复性能进行了定量评估/验证。此外，在钙离子存在的情况下，自我修复行为可以得到显著促进/增强。最后，体外细胞毒性分析表明的优异生物相容性表明，它是一种非常适合生物医学应用的有前途的自我修复材料。
