You Mingyu, Echeverry-Rendón Mónica, Zhang Lei, Niu Jialin, Zhang Jian, Pei Jia, Yuan Guangyin
National Engineering Research Center of Light Alloy Net Forming & State Key Laboratory of Metal Matrix Composite, Shanghai Jiao Tong University, Shanghai 200240, China.
National Engineering Research Center of Light Alloy Net Forming & State Key Laboratory of Metal Matrix Composite, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Innovation Medical Technology Co., Ltd., Shanghai 201306, China.
Mater Sci Eng C Mater Biol Appl. 2021 Jan;120:111734. doi: 10.1016/j.msec.2020.111734. Epub 2020 Nov 14.
Magnesium and its alloys have been recently used in biomedical applications such as orthopedic implants, whereas the weak corrosion resistance undermines their clinical efficacy. Herein, to address this critical challenge, the preparation of hierarchically structured hydroxyapatite-based coatings was proposed. Compact coatings were fabricated on a Mg alloy through a facile two-step method of chemical deposition of brushite precursor and subsequent hydrothermal conversion. A series of HA-based coatings were obtained with kinetic conversion process with formation mechanism revealed. The hydroxyapatite coating demonstrated the greatest corrosion resistance for Mg in electrochemical and long-term immersion tests, especially against pitting corrosion, attributable to its compact structure, alkaline degradation environment and self-induced growth capacity. The in vitro cytocompatibility and osteoinductivity were dictated. Additionally, anti-corrosion mechanisms were compared among different coating compositions and structures, along with their correlation with cellular response. Our study brings hints for a tailored surface design for resorbable biomedical device applications.
镁及其合金最近已被用于生物医学应用，如骨科植入物，但其耐腐蚀性较弱会影响其临床疗效。在此，为应对这一关键挑战，提出了制备具有分级结构的羟基磷灰石基涂层的方法。通过一种简便的两步法，即先化学沉积透钙磷石前驱体，随后进行水热转化，在镁合金上制备了致密涂层。通过动力学转化过程获得了一系列基于羟基磷灰石的涂层，并揭示了其形成机制。在电化学和长期浸泡试验中，羟基磷灰石涂层对镁表现出最大的耐腐蚀性，尤其是抗点蚀性能，这归因于其致密结构、碱性降解环境和自诱导生长能力。对体外细胞相容性和骨诱导性进行了研究。此外，还比较了不同涂层组成和结构之间的防腐机制，以及它们与细胞反应的相关性。我们的研究为可吸收生物医学设备应用的定制表面设计提供了思路。
