Centre for Research in Engineering and Surface Technology, Dublin Institute of Technology, Kevin Street, Dublin 8, Ireland.
School of Food Science and Environmental Health, Cathal Brugha Street, Dublin Institute of Technology, Dublin 1, Ireland.
J Mater Sci Mater Med. 2018 Aug 28;29(9):144. doi: 10.1007/s10856-018-6150-5.
This paper reports the corrosion resistant and cytocompatible properties of the hyaluronic acid-silane coating on AZ31 Mg alloy. In this study, the osteoinductive properties of high molecular weight hyaluronic acid (HA, 1-4 MDa) and the corrosion protection of silane coatings were incorporated as a composite coating on biodegradable AZ31 Mg alloy for orthopaedic applications. The multi-step fabrication of coatings first involved dip coating of a passivated AZ31 Mg alloy with a methyltriethoxysilane-tetraethoxysilane sol-gel to deposit a dense, cross-linked and corrosion resistant silane coating (AZ31-MT). The second step was to create an amine-functionalised surface by treating coated alloy with 3-aminopropyl-triethoxy silane (AZ31-MT-A) which facilitated the immobilisation of HA via EDC-NHS coupling reactions at two different concentrations i.e 1 mg.ml (AZ31-MT-A-HA1) and 2 mg.ml (AZ31-MT-A-HA2). These coatings were characterised by Fourier transform infrared spectroscopy, atomic force microscopy and static contact angle measurements which confirmed the successful assembly of the full coatings onto AZ31 Mg alloy. The influence of HA-silane coating on the corrosion of Mg alloy was investigated by electrical impedance spectroscopy and long-term immersion studies measurements in HEPES buffered DMEM. The results showed an enhanced corrosion resistance of HA functionalised silane coated AZ31 substrate over the uncoated equivalent alloy. Furthermore, the cytocompatibility of MC3T3-E1 osteoblasts was evaluated on HA-coated AZ31-MT-A substrates by live-dead staining, quantification of total cellular DNA content, scanning electron microscope and alkaline phosphatase activity. The results showed HA concentration-dependent improvement of osteoblast cellular response in terms of enhanced cell adhesion, proliferation and differentiation. These findings hold great promise in employing such biomimetic multifunctional coatings to improve the corrosion resistance and cytocompatibility of biodegradable Mg-based alloy for orthopaedic applications.
本文报道了透明质酸-硅烷涂层在 AZ31 镁合金上的耐腐蚀和细胞相容性。在这项研究中，高分子量透明质酸（HA，1-4MDa）的成骨诱导性能和硅烷涂层的腐蚀防护被整合到可生物降解的 AZ31 镁合金上作为复合涂层，用于骨科应用。涂层的多步制备首先涉及用甲基三甲氧基硅烷-四乙氧基硅烷溶胶-凝胶对钝化的 AZ31 镁合金进行浸涂，以沉积致密、交联且耐腐蚀的硅烷涂层（AZ31-MT）。第二步是通过用 3-氨丙基三甲氧基硅烷（AZ31-MT-A）处理涂覆的合金来制备胺功能化表面，这促进了 HA 通过 EDC-NHS 偶联反应固定在两个不同浓度下，即 1mg.ml（AZ31-MT-A-HA1）和 2mg.ml（AZ31-MT-A-HA2）。这些涂层通过傅里叶变换红外光谱、原子力显微镜和静态接触角测量进行了表征，证实了完整涂层成功组装到 AZ31 镁合金上。通过电化学阻抗谱和在 HEPES 缓冲 DMEM 中的长期浸泡研究测量，研究了 HA-硅烷涂层对镁合金腐蚀的影响。结果表明，HA 功能化硅烷涂层的 AZ31 基底的耐腐蚀性优于未涂覆的等效合金。此外，通过活/死染色、总细胞 DNA 含量的定量、扫描电子显微镜和碱性磷酸酶活性评估了 HA 涂层的 AZ31-MT-A 基底上 MC3T3-E1 成骨细胞的细胞相容性。结果表明，HA 浓度依赖性地改善了成骨细胞的细胞反应，表现为增强的细胞粘附、增殖和分化。这些发现为采用这种仿生多功能涂层来提高可生物降解的镁基合金的耐腐蚀性和细胞相容性以用于骨科应用提供了很大的希望。
