Antimicrobial Copper - Functional Surfaces and Factors of Toxicity

通过激光干涉表面结构精确调整表面参数、形貌和化学性质，在第一次提议中产生了细菌尺度的模型表面。使用这些，控制润湿，离子释放和细菌粘附在金属表面的表面参数进行了评估。此外，还对铜在细菌活力试验中的氧化行为以及激光熔覆铜与银的结合进行了实现和研究。调谐的材料和表面参数与这些表面的抗菌效率精确相关。这里描述的后续建议是由第一个建议的部分令人惊讶的结果所驱动的。这里的重点在于材料与细菌直接接触的作用，以及不同表面电位对接触杀灭的电化学影响。正如在第一个方案中定量显示的那样，细菌与金属表面之间的接触在很大程度上决定了杀灭率，因此在后续方案中将创建地形定制的铜表面。在这些问题上，将调查有效接触面积的变化是否以及如何影响杀伤率。在项目的第二部分，将通过激光干涉光刻和连续金属涂层来诱导具有控制电位差的化学表面图案。利用这些图案表面，通过材料组合和图案尺度的变化来研究电位差的影响。为了将其与抗菌效率联系起来，在所研究的表面上的细菌粘附将在显微镜下定量表征，与这些研究平行。鉴于危险细菌对抗生素的耐药性不断上升，以及利用抗菌材料与部分致命和高度传染性疾病作斗争，这项研究与社会特别相关。

By precisely tuning the surface parameters topography and chemistry using laser interference surface structuring, model surfaces on the scale of bacteria have been generated during the first proposal. Using these, the surface parameters that govern wetting, ion release and bacterial adhesion on metallic surfaces have been evaluated. In addition, the oxidation behavior of copper during viability tests with bacteria as well as the combination of copper and silver by laser cladding have been implemented and investigated on. The tuned material and surface parameters have been precisely correlated to the antimicrobial efficiency of these surfaces.The here described follow-up proposal is motivated by the partially surprising results from the first proposal. The emphasis here lies on the role of the immediate contact between material and bacteria as well as the electrochemical influence of differentiating surface potentials on the contact killing. As it has been quantitatively shown during the first proposal, that the contact between bacteria and metallic surface significantly governs the killing rate, topographically tailored copper surfaces will be created in the follow-up proposal. On these, it will be subject of investigation if and how the killing rate can be influenced by variation of the effective contact area. In the second part of the project, chemical surface pattern with controlled potential differences will be induced by laser interference lithography and consecutive metal coating. By using these patterned surfaces, the influence of potential differences will be studied by variation of material combination and pattern scale. In order to correlate it with antimicrobial efficiency, the bacterial adhesion on the investigated surfaces will be quantitatively characterized by microscope, parallel to these studies. This research is specifically relevant for the society in the light of rising antibiotics resistance of dangerous germs and the fight of partly deadly and highly infectious diseases by employing antimicrobial materials.