ARC Centre of Excellence for Electromaterials Science, University of Wollongong, Wollongong, Australia.
Acta Biomater. 2013 Nov;9(10):8671-7. doi: 10.1016/j.actbio.2012.12.025. Epub 2013 Jan 11.
Biodegradable magnesium alloys are advantageous in various implant applications, as they reduce the risks associated with permanent metallic implants. However, a rapid corrosion rate is usually a hindrance in biomedical applications. Here we report a facile two step procedure to introduce multifunctional, anti-corrosive coatings on Mg alloys, such as AZ31. The first step involves treating the NaOH-activated Mg with bistriethoxysilylethane to immobilize a layer of densely crosslinked silane coating with good corrosion resistance; the second step is to impart amine functionality to the surface by treating the modified Mg with 3-amino-propyltrimethoxysilane. We characterized the two-layer anticorrosive coating of Mg alloy AZ31 by Fourier transform infrared spectroscopy, static contact angle measurement and optical profilometry, potentiodynamic polarization and AC impedance measurements. Furthermore, heparin was covalently conjugated onto the silane-treated AZ31 to render the coating haemocompatible, as demonstrated by reduced platelet adhesion on the heparinized surface. The method reported here is also applicable to the preparation of other types of biofunctional, anti-corrosive coatings and thus of significant interest in biodegradable implant applications.
可生物降解的镁合金在各种植入物应用中具有优势，因为它们降低了与永久性金属植入物相关的风险。然而，在生物医学应用中，快速的腐蚀速率通常是一个障碍。在这里，我们报告了一种简便的两步法，在镁合金（如 AZ31）上引入多功能、耐腐蚀的涂层。第一步涉及用双（三乙氧基硅基）乙烷处理 NaOH 活化的镁，以固定一层具有良好耐腐蚀性的密集交联硅烷涂层；第二步是通过用 3-氨基丙基三甲氧基硅烷处理改性的镁来赋予表面胺官能团。我们通过傅里叶变换红外光谱、静态接触角测量和光学轮廓测量、动电位极化和交流阻抗测量来表征 AZ31 镁合金的双层防腐涂层。此外，肝素被共价键接到硅烷处理的 AZ31 上，使涂层具有血液相容性，如肝素化表面上血小板黏附减少所证明的那样。这里报道的方法也适用于制备其他类型的生物功能、耐腐蚀涂层，因此在可生物降解的植入物应用中具有重要意义。
