Improved corrosion performance of biodegradable magnesium in simulated inflammatory condition via drug-loaded plasma electrolytic oxidation coatings
Improved corrosion performance of biodegradable magnesium in simulated inflammatory condition via drug-loaded plasma electrolytic oxidation coatings
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DOI：
10.1016/j.matchemphys.2019.122003
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发表时间：
2020-01-01
影响因子：
4.6
通讯作者：
Mozafari, Masoud
中科院分区：
文献类型：
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作者：
Bordbar-Khiabani, Aidin;Yarmand, Benyamin;Mozafari, Masoud
镁及其合金是当今骨科应用中最常见的可生物降解材料之一。植入骨科器械后，炎症反应会在植入物附近产生过氧化氢和酸性环境。采用浸涂法在镁合金等离子体电解氧化膜上制备了一层具有抗炎作用的磷酸二氢钠（BSP）。利用X射线衍射（XRD）、傅里叶变换红外光谱（TIR）、配备能量色散X射线光谱的场发射扫描电子显微镜（FESEM-EDX）和原子力显微镜（AFM）进行表征研究。结果表明，BSP层成功地密封了PEO涂层。在正常和模拟炎症条件下，通过电化学阻抗谱（EIS）和动电位极化测试评价未涂覆和涂覆样品的耐腐蚀性。在模拟的炎症过程中，样品显示出增强的腐蚀速率相比，正常条件下。结果表明，与未涂覆的镁合金和PEO涂层相比，PEO/BSP涂层的耐腐蚀性能提高了2 ~ 3个数量级。浸泡试验表明，BSP涂层显著提高了PEO涂层镁合金在模拟体液（SEP）中的生物活性。并对载药涂层的体外释药行为进行了评价。
Magnesium and its alloys are nowadays one of the most common biodegradable materials for orthopedic applications. Following the implantation of an orthopedic device, near the implant hydrogen peroxide and acidic environment are generated by an inflammatory reaction. In this study, a betamethasone sodium phosphate (BSP) layer as an anti-inflammatory drug was prepared on plasma electrolytic oxidation (PEO) coatings by a dipcoating process on magnesium alloys. X-ray diffraction (XRD), Fourier transformation infrared spectroscopy TIR), field emission scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (FESEM-EDX) and atomic force microscopy (AFM) were utilized for characterization studies. The results showed that the BSP layer successfully sealed the PEO coating. The corrosion resistance of the uncoated and coated samples was evaluated by electrochemical impedance spectroscopy (EIS) and potentioclynamic polarization tests in normal and simulated inflammatory conditions. During the simulated inflammation, the samples indicated an enhanced corrosion rate compared to that of normal condition. The results in the inflammatory environment showed that the corrosion resistance of the PEO/BSP coating was remarkably improved by two or three orders of magnitude, compared with uncoated Mg alloy and the PEO coating. Immersion tests show that the BSP layer significantly improves the bioactivity of PEO-coated Mg alloy in simulated body fluid (SEP). Moreover, the in vitro release behavior of drug loaded PEO coating was evaluated.