镁合金表面白藜芦醇诱导羟基磷灰石涂层的制备与表征

Preparation and Characterization of Resveratrol-Induced Hydroxyapatite Coating on Magnesium Alloy Surface

为改善镁合金的细胞相容性和耐腐蚀性,期望能制备出一种可生物降解的医用材料。为此,利用白藜芦醇的诱导作用通过仿生矿化的方法在AZ31镁合金表面制得含白藜芦醇-羟基磷灰石(BLLC-HA)的复合涂层,采用动电位极化试验和氢气释放试验来测试样本的耐腐蚀性,采用MTT法和细胞形态观察法来评估样本的人体细胞相容性。动电位极化试验结果表明,与AZ31组(E_(corr)=-1.399 V)相比,AZ31-BLLC-HA(E_(corr)=-1.152 V)的腐蚀电位增加了247 mV,同时腐蚀电流密度降低了3个数量级。氢气释放试验显示AZ31、AZ31-BLLC-HA组平均氢气释放速率是1.41 mL/(cm^(2)·d)和0.41 mL/(cm^(2)·d)。MTT结果显示细胞增值率最高的是AZ31-BLLC-HA,且明显高于阴性对照组。研究表明,含羟基磷灰石-白藜芦醇复合涂层的AZ31镁合金其耐腐蚀性显著提高,该复合材料在模拟体液中的降解速率明显降低,同时含羟基磷灰石-白藜芦醇复合涂层的AZ31镁合金具备良好的细胞相容性。该复合涂层为医用生物材料表面的功能化提供了新思路。

In order to improve the cell compatibility and corrosion resistance of magnesium alloys, it was expected to prepare a biodegradable medical material in this work. Herein, a composite coating containing resveratrol-hydroxyapatite(BLLC-HA) was prepared on the surface of AZ31 magnesium alloy through a biomimetic mineralization method with the induction effect of resveratrol. Potentiodynamic polarization tests and hydrogen release tests were used to test the corrosion resistance of the coatings. Meanwhile, the MTT method and cell morphology observation method were used to evaluate the human cell compatibility of the samples. The potentiodynamic polarization test results showed that the corrosion potential of AZ31-BLLC-HA(E_(corr)=-1.152 V) increased by 247 mV compared with the AZ31 group(E_(corr)=-1.399 V), and the corrosion current density decreased by three orders of magnitude. The hydrogen release test showed that the average hydrogen release rate in the AZ31 and AZ31-BLLC-HA groups was 1.41 mL/(cm^(2)·d) and 0.41 mL/(cm^(2)·d), respectively. Moreover, the MTT results showed that the highest cell increment rate was found in AZ31-BLLC-HA, which was significantly higher than that in the negative controls. From the above, it could be obtained that the corrosion resistance of AZ31 magnesium alloy containing hydroxyapatite-resveratrol composite coating was significantly improved, and the degradation rate of this composite material in the simulated body fluid was significantly reduced. Besides, the AZ31 magnesium alloy containing hydroxyapatite-resveratrol composite coating had good cell compatibility. Generally, this composite coating could provide a new idea for functionalization of the surface of medical biomaterials.