Surface finishes on stainless steel reduce bacterial attachment and early biofilm formation: scanning electron and atomic force microscopy study

Abstract

Three common finishing treatments of stainless steel that are used for equipment during poultry processing were tested for resistance to bacterial contamination. Methods were developed to measure attached bacteria and to identify factors that make surface finishes susceptible or resistant to bacterial attachment and biofilm formation. Samples of the treated surfaces (sand-blasted, sanded, and electropolished) were exposed to natural bacterial populations from chicken carcass rinses to allow growth of bacteria and development of biofilms on the surfaces. The kinetics of bacterial growth during surface exposure was followed by UV-visible spectrophotometry, and counts of bacteria and early biofilm formation were measured following scanning electron microscopy (SEM). The surface morphology of the samples was analyzed by atomic force microscopy (AFM) with samples from each of the batches of treatments used in the SEM studies. Relative differences in the surface morphology, including fractal dimensions, Z ranges, roughness, and other measurements corresponded by treatment with the differences in reduction of bacterial counts shown by SEM. The surface types varied in affinity for bacteria, and both physical and electrochemical treatments improved resistance of stainless steel to bacterial attachment. Electropolished stainless steel was the least rough surface and showed significantly fewer bacterial cells and beginning biofilm formations than the other treated surfaces. Food safety could be improved if bacterial populations could be reduced during processing by increasing the use of materials that are resistant to bacterial contamination. These findings will aid equipment manufacturers and processors in selecting materials and finishes that are most resistant to bacteria and biofilm formation.

Antimicrobial properties of a nanostructured eggshell from a compost-nesting bird

“…Several studies have shown that the hydrophobicity and topography of a surface, e.g. an increased roughness (Arnold and Bailey, 2000) or nanostructural arrangements (Schumacher et al, 2007), decrease bacterial attachment in man-made and natural materials (Busscher and Weerkamp, 1987;Margel et al, 1993;Prime and Whitesides, 1993;Taylor et al, 1997;Wiencek and Fletcher, 1997). Thus, the eggshell topography of brush-turkeys may represent a way to prevent bacterial growth and potentially microbial infection without the use of chemicals, providing a new method for prevention of fouling on surfaces.…”

Biofilm-Related Infections: Bridging the Gap between Clinical Management and Fundamental Aspects of Recalcitrance toward Antibiotics

“…The biomaterial manufactur-ing process can also modify roughness and physicochemical properties and thus affect bacterial adhesion. Indeed, electropolished stainless steel reduces bacterial adhesion compared to that with sandblasted steel (254). Furthermore, the choice of the polymeric material, even without any modification, is of key importance.…”

Use of a stainless steel washer platform to study Acinetobacter baumannii adhesion and biofilm formation on abiotic surfaces

“…Previous work has shown that the coarseness found on the edges of stainless steel considerably enhances bacterial cell adhesion and biofilm formation compared with flat or polished surfaces (Arnold & Bailey, 2000). Our findings suggest that nosocomial infections might be reduced if bacterial deposition on medical surfaces is minimized by increasing the use of polished materials that are resistant to microbial colonization.…”