Controlled bacterial interaction to increase the antimicrobial efficiency of copper surfaces

控制细菌相互作用以提高铜表面的抗菌效率

• 批准号: 415956642
• 负责人: Professorin Dr. Karin Jacobs
• 金额: --
• 依托单位: Helmholtz-Institut für Pharmazeutische Forschung Saarland
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/415956642?language=en
• 关键词: Controlled; bacterial; interaction; increase; antimicrobial

The bacterial load on contact surfaces in public facilities such as hospitals can be reduced significantly by utilising antimicrobial copper alloys, which are lowering the spreading of infection diseases, particularly those caused by multi-resistant germs. The antimicrobial efficiency of copper containing surfaces is closely linked to their surface properties, which might have a beneficial or inhibitive effect on the bacterial killing.One objective of this project is to quantify the influence of the topographical and chemical properties of the surface on the antimicrobial efficiency of copper and its alloys. Why and how bacteria adhere to modified copper surface as well as how this is linked to the antimicrobial effect of the substrate needs to be thoroughly investigated. Laser-assisted surface processing enables the modulation of both surface topography and chemistry. By this, the purely electro-chemical bacteria killing mechanism is supplemented by topographical contact mechanic effects. Surface structures of similar scale as the bacteria are generated by Direct Laser Interference Patterning (DLIP) in order to selectively increase or reduce their contact area to the substrate. Using different pulse durations (10^-9 to 10^-15 s) provides the possibility to alter the surface chemistry due to varying laser/material interactions (ablation or melting) without significantly changing the produced surface topographies. The influence of this process on the wettability is quantitatively analysed using high-resolution microstructural and chemical characterisation and correlated to the bacterial killing efficiency of the surfaces. In order to achieve a better understanding of the interactions between the bacteria and the substrate, the adhesion of the germs on different modified surfaces is examined by recording force/distance curves using single-bacteria probes in AFM.Assessing the risk emanating from bacteria, which are developing resistances towards modified copper surfaces represents an additional objective of this study. Bacterial strains, which grew resistant to copper during the experiments, are tested for changes in their characteristic pathogenic properties like viability, proliferation and virulence. The examinations are also including the analysis of copper resistance mechanisms of isolated mutated strains by genome- and transcriptome essays. The knowledge gained about the connection of surface properties of copper alloys and their antimicrobial efficiency shall enable a more focused and efficient utilisation of these materials in antimicrobial applications.

通过使用抗菌铜合金，可以显着减少医院等公共设施接触表面的细菌负荷，从而减少感染性疾病的传播，特别是由多重耐药细菌引起的疾病。含铜表面的抗菌效率与其表面特性密切相关，这可能对细菌杀灭产生有益或抑制作用。该项目的一个目标是量化表面的形貌和化学特性对铜及其合金抗菌效率的影响。细菌为何以及如何粘附在改性铜表面上，以及这与基材的抗菌效果有何关系，都需要进行彻底的研究。激光辅助表面处理可以调节表面形貌和化学性质。由此，纯电化学杀菌机制得到了地形接触机械效应的补充。通过直接激光干涉图案化 (DLIP) 生成与细菌规模相似的表面结构，以便有选择地增加或减少细菌与基材的接触面积。使用不同的脉冲持续时间（10^-9 至 10^-15 秒）可以由于不同的激光/材料相互作用（烧蚀或熔化）而改变表面化学性质，而不会显着改变所产生的表面形貌。使用高分辨率微观结构和化学表征定量分析该过程对润湿性的影响，并将其与表面的细菌杀灭效率相关联。为了更好地了解细菌和基材之间的相互作用，通过使用 AFM 中的单细菌探针记录力/距离曲线来检查细菌在不同改性表面上的粘附。评估对改性铜表面产生抗性的细菌所产生的风险是本研究的另一个目标。在实验过程中对铜产生抗药性的细菌菌株被测试其致病特性（如活力、增殖和毒力）的变化。检查还包括通过基因组和转录组论文分析分离突变菌株的铜抗性机制。获得的有关铜合金表面特性与其抗菌效率之间关系的知识将使这些材料在抗菌应用中得到更集中和更有效的利用。