College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, China.
State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
J Mater Chem B. 2019 Sep 14;7(34):5237-5244. doi: 10.1039/c9tb00676a. Epub 2019 Aug 5.
As the hardest tissue in human body, enamel has attracted significant research interest in recent years. It has been acknowledged that the highly oriented arrangement of hydroxyapatite (HAp) crystallites of the enamel plays a crucial role owing to its excellent mechanical properties. So far, the preparation of enamel-like HAp crystallites on general substrates using mild conditions remains a challenge. Here, inspired by natural enamel, we developed a biomimetic, anodic alumina oxide (AAO)-assisted, double-layered gel system to fabricate well-oriented HAp crystals on universal surfaces. The one-directional ion flow was elaborately modulated for mineralization based on the synergistic effect of the double-layered gel and the AAO membrane, leading to highly oriented HAp crystallites. In addition, the introduction of polydopamine as a nucleating agent makes this method applicable for a wide range of substrates. The as-prepared minerals show a well-aligned enamel-like structure, exhibiting an elastic modulus of 52 GPa and nanohardness of 0.73 GPa, which are close to those of natural enamel. We envision that the strategy has potential applications for tooth repair and will provide guidelines for the mineralization of other inorganic minerals.
作为人体中最坚硬的组织，牙釉质近年来引起了广泛的研究兴趣。人们已经认识到，由于其优异的机械性能，牙釉质中羟基磷灰石（HAp）晶体的高度取向排列起着至关重要的作用。到目前为止，在温和条件下在普通基底上制备具有类似牙釉质的 HAp 晶体仍然是一个挑战。在这里，受天然牙釉质的启发，我们开发了一种仿生的、基于阳极氧化铝（AAO）的双层凝胶体系，在通用表面上制备具有良好取向的 HAp 晶体。基于双层凝胶和 AAO 膜的协同作用，精心调节单向离子流以进行矿化，从而得到高度取向的 HAp 晶体。此外，引入聚多巴胺作为成核剂，使这种方法适用于广泛的基底。所制备的矿物呈现出良好的类牙釉质结构，弹性模量为 52GPa，纳米硬度为 0.73GPa，接近天然牙釉质。我们设想该策略具有牙齿修复的应用潜力，并将为其他无机矿物的矿化提供指导。
