Institute of Materials Engineering, Poznan University of Technology, Poznan, Poland.
Department of Medical Microbiology, Poznan University of Medical Sciences, Poznan, Poland.
J Biomed Mater Res B Appl Biomater. 2021 Jun;109(6):829-840. doi: 10.1002/jbm.b.34748. Epub 2020 Oct 27.
Tantalum (Ta) and its application in biomaterials has been attracting more and more attention recently. It can be considered as a material for hard tissue implants. This study focuses on antimicrobial and surface characterization of micro-arc oxidized (MAO) nanocrystalline Ta compared with its microcrystalline equivalent. For the purposes of the investigation, x-ray diffractometry (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), wetting analysis, optical profilometry, corrosion resistance measurement, and antimicrobial tests were performed. Nanocrystalline Ta was fabricated using high-energy ball milling (HEBM) and pulse plasma sintering (PPS). The MAO process done at 250 V results in the formation of a porous oxide surface. An XRD analysis confirmed the presence of a Ta O oxide layer. Based on the SEM pictures, the obtained oxide layer was approximately 3-4 μm thick for nanocrystalline Ta substrate. For microcrystalline Ta, the oxide layer was thinner, in the range of 0.3-0.6 μm. The analysis of polarization curves showed a significant improvement of corrosion resistance for MAO nanocrystalline Ta (2.62 × 10 A/cm ) versus not oxidized nanocrystalline Ta (1.20 × 10 A/cm ). The surface roughness of MAO nanocrystalline Ta proved to be several times higher than that of unoxidized Ta. Wetting analysis showed that the oxide layer on the nanocrystalline substrate is hydrophilic. This research provides detailed information about MAO microcrystalline and MAO nanocrystalline Ta antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa. A significant decrease of S. aureus for MAO nanocrystalline Ta (control 10,435 ± 981 vs. sample 3,453 ± 130) was noticed. No significant difference was noticed for MAO microcrystalline and nanocrystalline Ta tested for P. aeruginosa.
钽（Ta）及其在生物材料中的应用最近引起了越来越多的关注。它可以被认为是一种用于硬组织植入物的材料。本研究主要关注微弧氧化（MAO）纳米晶 Ta 与等晶微 Ta 的抗菌和表面特性。为此，进行了 X 射线衍射（XRD）、扫描电子显微镜（SEM）、原子力显微镜（AFM）、润湿分析、光学轮廓仪、耐腐蚀性测量和抗菌测试。纳米晶 Ta 通过高能球磨（HEBM）和脉冲等离子烧结（PPS）制备。在 250V 下进行的 MAO 工艺导致形成多孔氧化物表面。XRD 分析证实存在 Ta O 氧化物层。根据 SEM 照片，对于纳米晶 Ta 基底，获得的氧化物层的厚度约为 3-4μm。对于微晶 Ta，氧化物层更薄，在 0.3-0.6μm 范围内。极化曲线分析表明，MAO 纳米晶 Ta 的耐腐蚀性有显著提高（2.62×10 A/cm ），而非氧化的纳米晶 Ta 的耐腐蚀性（1.20×10 A/cm ）。MAO 纳米晶 Ta 的表面粗糙度证明比未氧化的 Ta 高几个数量级。润湿分析表明，纳米晶基底上的氧化物层具有亲水性。本研究提供了关于 MAO 微晶和 MAO 纳米晶 Ta 对抗金黄色葡萄球菌和铜绿假单胞菌的抗菌活性的详细信息。观察到 MAO 纳米晶 Ta 对金黄色葡萄球菌的活性显著降低（对照 10,435±981 对样品 3,453±130）。对 MAO 微晶和纳米晶 Ta 进行铜绿假单胞菌测试时，没有发现显著差异。
