Enhancing antibacterial properties of PEEK surfaces: Laser-induced and machine-learning assessed

Creating sub-micrometer structures on material surfaces to achieve physical antibacterial effects is of significant importance and value across various fields, including prosthetics for bone repair and implants. High-performance polymers such as polyetheretherketone (PEEK), which lack inherent chemical antibacterial properties, can greatly benefit from exploring physical antibacterial mechanisms to extend their applications in medical, healthcare, and food-related domains. This study employs femtosecond laser direct writing technology to fabricate antibacterial microstructures on PEEK surfaces. By varying the laser parameters, we can predictably control and modify the resulting surface microstructures and their physical properties. Additionally, we have trained a machine learning model to predict the antibacterial efficacy of these surfaces based on two-dimensional scanning electron microscope images, enabling us to identify the most promising antibacterial surfaces. Our combined approach has produced PEEK surfaces with antibacterial efficacy of up to 77.8% against Staphylococcus aureus and 92.3% against Escherichia coli. This work advances our understanding of how surface microstructure influences antibacterial performance, paving the way for the systematic design and production of antibacterial materials.