3D periodic microscale structures on binary copper-nickel alloys via fs-DLIP: impact on E. coli-substrate interaction

Authors

Ahmed A.S., Wältermann S., Delfino P.M., Müller D.W., Audinot J.N., Pierson J.F., Mücklich F.

Reference

Materials and Design, vol. 258, art. no. 114545, 2025

Description

In response to the rise of multidrug-resistant infections, researchers are increasingly focusing on modifying material surfaces through chemical or topographical changes to limit microbial spread. Copper and its alloys are particularly valued for their antimicrobial properties, playing a key role in combating pathogen transmission. To explore the potential of enhancing the antibacterial performance of copper-based alloys, this study focuses on surface modification of binary copper-nickel alloys. The goal is to create periodic microstructures at the scale of a single bacterial cell (Escherichia coli) and explore the bacteria-substrate interaction. Two copper-nickel alloy compositions with 10 and 30 wt-% nickel are selected to assess the impact of nickel on laser-material interaction. Additionally, two surface structures, lines and honeycomb, are fabricated to evaluate how structure type affects bacterial interaction. Results show that the line-like structures on the 10 wt-% nickel alloy enhance bacterial killing, while honeycomb structures show no improvement. Conversely, both laser-structured copper-nickel alloys with 30 wt-% nickel exhibit decreased bacterial killing, attributed to the reduced surface copper concentration (below 60 wt-%) as confirmed by chemical analyses. These findings highlight the importance of copper content and structural compatibility for effective contact-killing performance.

Link

doi:10.1016/j.matdes.2025.114545