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.

镁及其合金近来已用于生物医学应用中，例如整形外科植入物，而耐腐蚀性较弱则削弱了它们的临床功效。在此，为了解决这一关键挑战，提出了制备基于分层结构的羟基磷灰石基涂料的方法。通过镁锌矿前体的化学沉积和随后的水热转化的简便的两步法在Mg合金上制备致密涂层。通过动力学转化工艺获得了一系列HA基涂层，揭示了形成机理。羟基磷灰石涂层由于其紧凑的结构，在电化学和长期浸入测试中表现出对镁最大的耐腐蚀性，尤其是对点蚀的抵抗力。碱性降解环境和自生生长能力。的规定了体外细胞相容性和骨诱导性。另外，比较了不同涂料组成和结构之间的防腐机理，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的应用提供了量身定制的表面设计的暗示。