Kim Hee-Kyeong, Baek Hyeon Woo, Park Hyun-Ha, Cho Young-Sam
Department of Mechanical Engineering, College of Engineering, Wonkwang University, 460 Iksandae-ro, Iksan, Jeonbuk 54538, Republic of Korea.
Department of Mechanical Engineering, College of Engineering, Wonkwang University, 460 Iksandae-ro, Iksan, Jeonbuk 54538, Republic of Korea; MECHABIO Group, Wonkwang University, 460 Ikandae-ro, Iksan, Jeonbuk 54538, Republic of Korea.
Colloids Surf B Biointerfaces. 2024 Feb;234:113729. doi: 10.1016/j.colsurfb.2023.113729. Epub 2023 Dec 25.
Biofilms formed owing to the attachment of bacteria to surfaces have caused various problems in industries such as marine transportation/logistics and medicine. In response, many studies have been conducted on bactericidal surfaces, and nanostructured surfaces mimicking cicada and dragonfly wings are emerging as candidates for mechano-bactericidal surfaces. In specific circumstances involving mechano-bactericidal activity, certain nanostructured surfaces could exhibit their bactericidal effects by directly deforming the membranes of bacteria that adhere to these nanostructures. Additionally, in most cases, debris of bacterial cells may accumulate on these nanostructured surfaces. Such accumulation poses a significant challenge: it diminishes the mechano-bactericidal effectiveness of the surface, as it hinders the direct interaction between the nanostructures and any new bacteria that attach subsequently. In specific circumstances involving mechano-bactericidal activity, certain nanostructured surfaces could exhibit their bactericidal effects by directly deforming the membranes of bacteria that adhere to these nanostructures. Additionally, in most cases, debris of bacterial cells may accumulate on these nanostructured surfaces. Such accumulation poses a significant challenge: it diminishes the mechano-bactericidal effectiveness of the surface, as it hinders the direct interaction between the nanostructures and any new bacteria that attach subsequently.In other words, there is a need for strategies to remove the accumulated bacterial debris in order to sustain the mechano-bactericidal effect of the nanostructured surface. In this study, hierarchical micro/nano-structured surface (echinoid-shaped nanotextures were formed on Al micro-particle's surfaces) was fabricated using a simple pressure-less sintering method, and effective bactericidal efficiency was shown against E. coli (97 ± 3.81%) and S. aureus (80 ± 9.34%). In addition, thermal cleaning at 500 °C effectively eliminated accumulated dead bacterial debris while maintaining the intact AlO nanostructure, resulting in significant mechano-bactericidal activity (E. coli: 89 ± 6.86%, S. aureus: 75 ± 8.31%). As a result, thermal cleaning maintains the intact nanostructure and allows the continuance of the mechano-bactericidal effect. This effect was consistently maintained even after five repetitive use (E. coli: 80 ± 16.26%, S. aureus: 76 ± 12.67%).
由于细菌附着在表面而形成的生物膜在海洋运输/物流和医学等行业引发了各种问题。对此,人们对杀菌表面进行了许多研究,模仿蝉和蜻蜓翅膀的纳米结构表面正成为机械杀菌表面的候选材料。在涉及机械杀菌活性的特定情况下,某些纳米结构表面可以通过直接使附着在这些纳米结构上的细菌细胞膜变形来发挥其杀菌作用。此外,在大多数情况下,细菌细胞碎片可能会积聚在这些纳米结构表面。这种积聚带来了一个重大挑战:它会降低表面的机械杀菌效果,因为它阻碍了纳米结构与随后附着的任何新细菌之间的直接相互作用。在涉及机械杀菌活性的特定情况下,某些纳米结构表面可以通过直接使附着在这些纳米结构上的细菌细胞膜变形来发挥其杀菌作用。此外,在大多数情况下,细菌细胞碎片可能会积聚在这些纳米结构表面。这种积聚带来了一个重大挑战:它会降低表面的机械杀菌效果,因为它阻碍了纳米结构与随后附着的任何新细菌之间的直接相互作用。换句话说,需要有策略来清除积累的细菌碎片,以维持纳米结构表面的机械杀菌效果。在本研究中,使用简单的无压烧结方法制备了分级微/纳米结构表面(在铝微粒表面形成海胆状纳米纹理),并对大肠杆菌(97±3.81%)和金黄色葡萄球菌(80±9.34%)显示出有效的杀菌效率。此外,在500℃进行热清洗有效地消除了积累的死亡细菌碎片,同时保持了完整的氧化铝纳米结构,从而产生了显著的机械杀菌活性(大肠杆菌:89±6.86%,金黄色葡萄球菌:75±8.31%)。结果,热清洗保持了完整的纳米结构,并使机械杀菌效果得以持续。即使经过五次重复使用,这种效果也能持续保持(大肠杆菌:80±16.26%,金黄色葡萄球菌:76±12.67%)。