RMIT University, School of Engineering, Melbourne, Victoria, 3000, Australia; CSIRO, Manufacturing, Clayton, Victoria, 3168, Australia.
RMIT University, School of Science, Melbourne, Victoria, 3000, Australia.
Biomaterials. 2022 Jan;280:121271. doi: 10.1016/j.biomaterials.2021.121271. Epub 2021 Nov 25.
Conventional copper (Cu) metal surfaces are well recognized for their bactericidal properties. However, their slow bacteria-killing potency has historically excluded them as a rapid bactericidal material. We report the development of a robust bulk superhydrophilic micro-nano hierarchical Cu structure that possesses exceptional bactericidal efficacy. It resulted in a 4.41 log reduction (>99.99%) of the deadly Staphylococcus aureus (S. aureus) bacteria within 2 min vs. a 1.49 log reduction (96.75%) after 240 min on common Cu surfaces. The adhered cells exhibited extensive blebbing, loss of structural integrity and leakage of vital intracellular material, demonstrating the rapid efficacy of the micro-nano Cu structure in destructing bacteria membrane integrity. The mechanism was attributed to the synergistic degradation of the cell envelope through enhanced release and therefore uptake of the cytotoxic Cu ions and the adhesion-driven mechanical strain due to its rapid ultimate superhydrophilicity (contact angle drops to 0° in 0.18 s). The scalable fabrication of this micro-nano Cu structure was enabled by integrating bespoke precursor alloy design with microstructure preconditioning for dealloying and demonstrated on 2000 mm Cu surfaces. This development paves the way to the practical exploitation of Cu as a low-cost antibiotic-free fast bactericidal material.
传统的铜（Cu）金属表面因其杀菌性能而广为人知。然而，其缓慢的杀菌效力在历史上使其无法成为快速杀菌材料。我们报告了一种强大的块状超亲水微纳分级 Cu 结构的开发，该结构具有出色的杀菌功效。与普通 Cu 表面 240 分钟后 1.49 对数减少（96.75%）相比，它在 2 分钟内将致命的金黄色葡萄球菌（S. aureus）细菌减少了 4.41 对数（>99.99%）。附着的细胞表现出广泛的起泡、结构完整性丧失和重要细胞内物质泄漏，表明微纳 Cu 结构在破坏细菌膜完整性方面具有快速的功效。该机制归因于通过增强细胞毒性 Cu 离子的释放和因此摄取以及由于其快速的最终超亲水性（接触角在 0.18 秒内降至 0°）而导致的粘附驱动的机械应变，从而协同降解细胞包膜。通过将定制的前驱体合金设计与脱合金的微观结构预处理相结合，实现了这种微纳 Cu 结构的规模化制造，并在 2000mm Cu 表面上进行了演示。这一发展为将 Cu 作为一种低成本、无抗生素的快速杀菌材料进行实际应用铺平了道路。
