Surface Modification of Brass via Ultrashort Pulsed Direct Laser Interference Patterning and Its Effect on Bacteria-Substrate Interaction

• DOI: 10.1021/acsami.3c04801
• Publication Date: 2023-07-19T16:16:13Z
• Authors: Aisha Saddiqa Ahmed; Daniel Wyn Müller; Stephanie Bruyere; Anne Holtsch; Frank Müller; Jenifer Barrirero; Kristina Brix; Sylvie Migot; Ralf Kautenburger; Karin Jacobs; Jean-François Pie...; Frank Mücklich
• Keywords: brass; ultrashort pulsed direct laser interference patterning; femtosecond pulse duration; Bacteria; Surface Properties; Lasers; 500; zinc oxide; 3. Good health; Anti-Bacterial Agents; Zinc; nanoscale chemical modification; antibacterial; copper oxides; Escherichia coli; Alloys; Humans; nanoscale heat-affected zone; Copper

In recent decades, antibiotic resistance has become a crucial challenge for human health. One potential solution to this problem is the use of antibacterial surfaces, i.e., copper and copper alloys. This study investigates the antibacterial properties of brass that underwent topographic surface functionalization via ultrashort pulsed direct laser interference patterning. Periodic line-like patterns in the scale range of single bacterial cells were created on brass with a 37% zinc content to enhance the contact area for rod-shaped Escherichia coli (E. coli). Although the topography facilitates attachment of bacteria to the surface, reduced killing rates for E. coli are observed. In parallel, a high-resolution methodical approach was employed to explore the impact of laser-induced topographical and chemical modifications on the antibacterial properties. The findings reveal the underlying role of the chemical modification concerning the antimicrobial efficiency of the Cu-based alloy within the superficial layers of a few hundred nanometers. Overall, this study provides valuable insight into the effect of alloy composition on targeted laser processing for antimicrobial Cu-surfaces, which facilitates the thorough development and optimization of the process concerning antimicrobial applications.