Multi-criteria evaluation of ASTM E2562-based dynamic biofilm assay and JIS Z-2801 standards for assessing the antibacterial performance of modified AISI 304 stainless steel surfaces

This research evaluates the functionalisation of AISI 304 stainless steel via surface engineering, including oxy-nitrocarburising and electrodeposition from ethylene glycol-based electrolytes to produce silver, copper, nickel, and chromium–cobalt oxide coatings. Utilising an Analytic Hierarchy Process (AHP) framework, the study systematically compares two standardised methodologies: ASTM E2562 -based dynamic biofilm assay and JIS Z-2801 for static contact activity. The multi-criteria analysis integrates experimental data with operational parameters like reproducibility, robustness, and cost. Results demonstrate that both standards effectively discriminate between treatments, though nickel and chromium–cobalt coatings achieve superior performance against microbial colonisation. AHP reveals a preference for ASTM E2562-based dynamic biofilm assay when prioritising environmental representativeness in hydrodynamic systems. By validating these strategies through structured decision-making, this work provides a robust engineering approach for selecting antimicrobial finishes, optimising resource allocation for high-performance components in marine and industrial sectors.