School of Engineering, Plymouth University, Plymouth, UK.
School of Mechanical Engineering and Built Environment, University of Derby, Derby, UK.
Nanotoxicology. 2020 Feb;14(1):97-110. doi: 10.1080/17435390.2019.1665727. Epub 2019 Sep 30.
Medical grade titanium alloy, Ti-6Al-4V, with TiO nanotubes (TiO-NTs) grown on the surface and then decorated with silver nanoparticles (Ag NPs) is proposed to enhance the antimicrobial properties of the bone/dental implants. However, the decoration with Ag NPs is not consistent and there are concerns about the direct contact of Ag NPs with human tissue. The aim of this study was to achieve a more even coverage of Ag NPs on TiO-NTs and determine their biocidal properties against , with and without a top coat of nano hydroxyapatite (nHA). The decoration with Ag NPs was optimised by adjusting the incubation time of the TiO-NTs in a silver ammonia solution, and using biocompatible δ-gluconolactone as a reducing agent. The optimum incubation in silver ammonia was 7min, and resulted in evenly distributed Ag NPs with an average diameter of 47.5±1.7nm attached to the surface of the nanotubes. The addition of nHA did not compromise the antimicrobial properties of the materials; high-resolution electron microscopy showed did not grow on the composite with nHA and with >80% biocidal activity measured by the LIVE/DEAD assay, also limited lactate production. Dialysis experiment confirmed the stability of the coatings, and showed a slow release of dissolved silver (3.27±0.15μg/L over 24h) through the top coat of nHA.
医用级钛合金 Ti-6Al-4V，表面生长 TiO 纳米管（TiO-NTs），然后用银纳米颗粒（Ag NPs）进行修饰，以提高骨/牙科植入物的抗菌性能。然而，Ag NPs 的修饰并不一致，并且人们担心 Ag NPs 会直接与人体组织接触。本研究旨在实现 TiO-NTs 上 Ag NPs 更均匀的覆盖，并确定其对 的杀菌特性，有无纳米羟基磷灰石（nHA）的顶层涂层。通过调整 TiO-NTs 在银氨溶液中的孵育时间，并使用生物相容性 δ-葡萄糖酸内酯作为还原剂，优化了 Ag NPs 的修饰。在银氨中的最佳孵育时间为 7min，结果是均匀分布的 Ag NPs，平均直径为 47.5±1.7nm，附着在纳米管表面。添加 nHA 并未损害材料的抗菌性能；高分辨率电子显微镜显示 不会在含有 nHA 的复合材料上生长，通过 LIVE/DEAD 测定法测量，其杀菌活性>80%，也可限制乳酸盐的产生。透析实验证实了涂层的稳定性，并通过 nHA 的顶层涂层显示出溶解银的缓慢释放（24 小时内释放 3.27±0.15μg/L）。
