Science and Engineering Faculty, Queensland University of Technology, Brisbane, Queensland 4000, Australia.
Institute for Future Environments, Queensland University of Technology, Brisbane, Queensland 4000, Australia.
ACS Biomater Sci Eng. 2020 Jun 8;6(6):3608-3618. doi: 10.1021/acsbiomaterials.0c00348. Epub 2020 May 19.
With the rise of bacterial and viral infections including the recent outbreak of coronavirus, the requirement for novel antimicrobial strategies is also rising with urgency. To solve this problem, we have used a wet etching technique to fabricate 23 nm wide nanostructures randomly aligned as ridges on aluminum (Al) 6063 alloy surfaces. The surfaces were etched for 0.5, 1, and 3 h. The surfaces were characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy, contact angle goniometry, nanoindentation and atomic force microscopy. Strains of the Gram negative bacteria and the Gram positive bacteria were used to evaluate the bacterial attachment behavior. For the first time, common respiratory viruses, respiratory syncytial virus (RSV) and rhinovirus (RV), were investigated for antiviral activity on nanostructured surfaces. It was found that the etched Al surfaces were hydrophilic and the nanoscale roughness enhanced with the etching time with ranging from 69.9 to 995 nm. Both bacterial cells of and were physically deformed and were nonviable upon attachment after 3 h on the etched Al 6063 surface. This nanoscale surface topography inactivated 92 and 87% of the attached and cells, respectively. The recovery of infectious RSV was also reduced significantly within 2 h of exposure to the nanostructured surfaces compared to the smooth Al control surfaces. There was a 3-4 log reduction in the viability counts of rhinovirus after 24 h on the nanostructured surfaces. The nanostructured surfaces exhibited excellent durability as the surfaces sustained 1000 cycles of 2000 μN load without any damage. This is the first report that has shown the combined antibacterial and antiviral property of the nanostructured surface with excellent nanomechanical properties that could be potentially significant for use in hospital environments to stop the spread of infections arising from physical surfaces.
随着细菌和病毒感染（包括最近爆发的冠状病毒）的增加，对新型抗菌策略的需求也迫在眉睫。为了解决这个问题，我们使用湿法刻蚀技术在铝（Al）6063 合金表面制造了随机排列的 23nm 宽纳米结构，这些纳米结构呈脊状。表面的刻蚀时间分别为 0.5、1 和 3 小时。使用扫描电子显微镜、能量色散 X 射线光谱、接触角测角法、纳米压痕和原子力显微镜对表面进行了表征。使用革兰氏阴性菌 和革兰氏阳性菌 来评估细菌的附着行为。这是第一次研究常见的呼吸道病毒，呼吸道合胞病毒（RSV）和鼻病毒（RV）在纳米结构表面上的抗病毒活性。结果发现，刻蚀后的 Al 表面亲水，纳米级粗糙度随刻蚀时间的增加而增加，范围从 69.9nm 到 995nm。在刻蚀的 Al 6063 表面上，经过 3 小时的附着， 和 两种细菌细胞都发生了物理变形，且无法存活。这种纳米级表面形貌使附着的 和 细胞分别失活了 92%和 87%。与光滑的 Al 对照表面相比，暴露在纳米结构表面 2 小时内，恢复的 RSV 的传染性也显著降低。在纳米结构表面上，鼻病毒的存活计数在 24 小时后减少了 3-4 个对数。纳米结构表面具有出色的耐用性，在没有任何损坏的情况下，可承受 1000 次 2000μN 负载的循环。这是首次报道纳米结构表面具有抗菌和抗病毒的综合特性，以及出色的纳米力学性能，这可能对医院环境中阻止物理表面感染传播具有重要意义。
