Increasing Antibacterial Efficiency of Cu Surfaces by targeted Surface Functionalization via Ultrashort Pulsed Direct Laser Interference Patterning

• Published in: Advanced materials interfaces Vol. 8; no. 5
• Main Authors: Müller, Daniel W., Lößlein, Sarah, Terriac, Emmanuel, Brix, Kristina, Siems, Katharina, Moeller, Ralf, Kautenburger, Ralf, Mücklich, Frank
• Format: Journal Article
• Language: English
• Published: Weinheim John Wiley & Sons, Inc 01.03.2021; Wiley
• Subjects: antimicrobial copper surfaces; Bacteria; Biological Physics; Biotechnology; Cancer; Cellular Biology; Chemical Physics; Copper; E coli; Interference; laser surface structuring; Life Sciences; Microorganisms; Optics; Physics; Properties (attributes); Subcellular Processes; Substrates; ultrashort pulsed direct laser interference patterning; Wettability; laser surface structuring; ultrashort pulsed direct laser interference patterning; antimicrobial copper surfaces
• ISSN: 2196-7350; 2196-7350
• DOI: 10.1002/admi.202001656

Copper (Cu) exhibits great potential for application in the design of antimicrobial contact surfaces aiming to reduce pathogenic contamination in public areas as well as clinically critical environments. However, current application perspectives rely purely on the toxic effect of emitted Cu ions, without considering influences on the interaction of pathogenic microorganisms with the surface to enhance antimicrobial efficiency. In this study, it is investigated on how antibacterial properties of Cu surfaces against Escherichia coli can be increased by tailored functionalization of the substrate surface by means of ultrashort pulsed direct laser interference patterning (USP‐DLIP). Surface patterns in the scale range of single bacteria cells are fabricated to purposefully increase bacteria/surface contact area, while parallel modification of the surface chemistry allows to involve the aspect of surface wettability into bacterial attachment and the resulting antibacterial effectivity. The results exhibit a delicate interplay between bacterial adhesion and the expression of antibacterial properties, where a reduction of bacterial cell viability of up to 15‐fold can be achieved for E. coli on USP‐DLIP surfaces in comparison to smooth Cu surfaces. Thereby, it can be shown how the antimicrobial properties of copper surfaces can be additionally enhanced by targeted surface functionalization. Antimicrobial efficiency of copper (Cu) surfaces against Escherichia coli is increased up to 15‐fold by surface structuring in the scale of single bacteria cells via ultrashort pulsed direct laser interference patterning. Increased bacterial killing can mainly be attributed to altered Cu sensitivity due to different contact situations involving both available contact area and surface wettability.