Role of the Surface Nanoscale Roughness of Stainless Steel on Bacterial Adhesion and Microcolony Formation

Abstract

Hospital-acquired infections can cause serious complications and are a severe problem because of the increased emergence of antibiotic-resistant bacteria. Biophysical modification of the material surfaces to prevent or reduce bacteria adhesion is an attractive alternative to antibiotic treatment. Since stainless steel is a widely used material for implants and in hospital settings, in this work, we used stainless steel to investigate the effect of the material surface topographies on bacterial adhesion and early biofilm formation. Stainless steel samples with different surface roughnesses Rq in a range of 217.9–56.6 nm (Ra in a range of 172.5–45.2 nm) were fabricated via electropolishing and compared for adhesion of bacterial pathogens Pseudomonas aeruginosa and Staphylococcus aureus. It was found that the number of viable cells on the untreated rough surface was at least 10-fold lower than those on the electropolished surfaces after 4 h of incubation time for P. aeruginosa and 15-fold lower for S. aureus. Fluorescence images and scanning electron microscopy images revealed that the bacterial cells tend to adhere individually as single cells on untreated rough surfaces. In contrast, clusters of the bacterial cells (microcolonies) were observed on electropolished smooth surfaces. Our study demonstrates that nanoscale surface roughness can play an important role in restraining bacterial adhesion and formation of microcolonies.

Reduced bacterial adhesion with parylene coating: Potential implications for Micra transcatheter pacemakers

“…Within the scope of the experiment, limited attempts were made to understand how material properties may have contributed to the findings. We found that parylene had a significantly reduced contact angle and appeared smoother in SEM images as compared to bare titanium, potentially providing less opportunity for biofilm formation 20–22 . However, we observed the opposite relationship between contact angle and surface smoothness when parylene was compared to polyurethane.…”

Bacterial Adhesion on Soft Materials: Passive Physicochemical Interactions or Active Bacterial Mechanosensing?

“…In addition to bacterial mechanosensing systems, substratum physicochemical parameters, such as surface charge, hydrophobicity, roughness, topography, and chemistry have been found to influence bacterial adhesion and the initial biofilm formation . Very recently it has been reported that mechanical stiffness of the substratum influences bacterial adhesion suggesting an interesting alternative approach in the development of antibacterial surfaces.…”

Evaluation of Surface Roughness and <i>Streptococcus mutans</i> Adhesion to Bulk-Fill Resin Composites Polished with Different Systems

“…Similarly, it has been reported that S. aureus adhesion was strongly correlated to the surface roughness [49]. Furthermore, qualitative and quantitative adhesion analyses on different surfaces demonstrated significant aggregation of bacterial cells on untreated surfaces than on electro polished smooth surfaces [50]. Conversely, Eick et al [51] disagreed with this relationship and reported that nocorrelation was observed between surface roughness and the number of colony forming units (CFU) of S. mutans in their study.…”