Toplitsch Daniela, Lackner Jürgen Markus, Schwan Alexander Michael, Hinterer Andreas, Stögmüller Philipp, Horn Kerstin, Fritzlar Natalie, Pfuch Andreas, Kittinger Clemens
D&R-Institute of Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, 8010 Graz, Austria.
Joanneum Research Forschungsges m.b.H., Institute of Surface Technologies and Photonics, Laser and Plasma Processing, Leobner Str. 94, 8712 Niklasdorf, Austria.
Materials (Basel). 2021 Oct 28;14(21):6488. doi: 10.3390/ma14216488.
In this study, assessment of the antimicrobial activity of a novel, plasma-cured 2.5% (/) Cu(NO)-containing sol-gel surface was performed. In contrast to state-of-the-art sol-gel coatings, the plasma curing led to a gradient in cross-linking with the highest values at the top of the coating. As a result, the coating behaved simultaneously hard, scratch-resistant, and tough, the latter due to the more flexible bulk of the coating toward the substrate. Further, the diffusion and permeation through the coating also increased toward the substrate. In our study, tests according to ISO 22196 showed antibacterial activity of the 2.5% (/) Cu(NO)-containing sol-gel surface against all bacterial strains tested, and we expanded the testing further using a "dry" evaluation without an aqueous contact phase, which confirmed the antimicrobial efficacy of the 2.5% (/) Cu(NO)-containing sol-gel surface. However, further investigation under exposure to soiling with the addition of 0.3% albumin, used to simulate organic load, led to a significant impairment in the antibacterial effect under both tested conditions. Furthermore, re-testing of the surface after disinfection with 70% ethanol led to a total loss of antibacterial activity. Our results showed that besides the mere application of an antimicrobial agent to a surface coating, it is also necessary to consider the future use of these surfaces in the experimental phase combining industry and science. Therefore, a number of tests corresponding to the utilization of the surface should be obligative on the basis of this assessment.
在本研究中，对一种新型的、经等离子体固化的含2.5%（/）硝酸铜的溶胶-凝胶表面的抗菌活性进行了评估。与最先进的溶胶-凝胶涂层不同，等离子体固化导致涂层交联形成梯度，涂层顶部的交联值最高。结果，该涂层同时表现出坚硬、耐刮擦和坚韧的特性，后者是由于涂层朝向基材的主体部分更具柔韧性。此外，通过涂层的扩散和渗透也朝着基材方向增加。在我们的研究中，根据ISO 22196进行的测试表明，含2.5%（/）硝酸铜的溶胶-凝胶表面对所有测试的细菌菌株均具有抗菌活性，并且我们进一步使用无水性接触相的“干燥”评估方法进行了测试，这证实了含2.5%（/）硝酸铜的溶胶-凝胶表面的抗菌效果。然而，在添加0.3%白蛋白以模拟有机负荷的污染条件下进行的进一步研究表明，在两种测试条件下抗菌效果均显著受损。此外，用70%乙醇消毒后对该表面进行重新测试导致抗菌活性完全丧失。我们的结果表明，除了在表面涂层上单纯应用抗菌剂外，在工业与科学相结合的实验阶段还需要考虑这些表面的未来使用情况。因此，基于这种评估，对应于表面使用的一些测试应该是必须的。
