Evaluation of anti-biofilm properties of SUS316L fabricated by 3D printing and the effect of PE resin application

Biofilms are complex, slime-like structures composed of bacteria, extracellular polymeric substances (EPS), and water. Their formation on material surfaces poses serious challenges, such as material degradation, corrosion, and increased risk of infection—especially in medical and industrial environments. As biofilm development is highly dependent on interactions between bacterial cells and the substrate surface, modifying material properties offers a promising strategy for biofilm control. This study explores the anti-biofilm performance of SUS316L stainless steel surfaces fabricated using the selective laser sintering (SLS) method under various scan speeds. These differences in scan speeds resulted in changes to surface roughness and morphology. In addition, ultra-high-molecular-weight polyethylene (UHMW-PE) coatings were applied to selected specimens to evaluate their influence on biofilm adhesion. To assess biofilm formation, bacterial samples were cultivated on the specimens, stained with crystal violet (CV), and quantified using an optical plate reader. The results revealed that the surface roughness of SLS-fabricated SUS316L influenced the extent of biofilm attachment. Notably, smoother surfaces obtained at specific scan speeds showed reduced biofilm accumulation. Furthermore, the wettability of UHMW-PE-coated samples was found to correlate strongly with biofilm suppression. Hydrophobic surfaces tended to resist biofilm formation more effectively. These findings demonstrate that both surface topography and wettability significantly influence bacterial adhesion and subsequent biofilm growth. By tuning material processing parameters and applying functional coatings, it may be possible to engineer surfaces that inherently resist biofilm formation. This research provides foundational insights into the development of next-generation materials for hygienic and medical applications. The results are expected to contribute to the design of safer medical devices and equipment by minimizing biofilm-related complications through material-level interventions.