Strength of bacterial adhesion on nanostructured surfaces quantified by substrate morphometry

Area of Science:

• Materials Science
• Microbiology
• Surface Science

Background:

• Microbial adhesion and biofilm formation are significantly influenced by substrate surface properties, particularly topography.
• Quantifying the relationship between surface topography and bacterial adhesion is challenging due to difficulties in measuring both parameters.

Purpose of the Study:

• To quantitatively link nanoscale surface topography with bacterial adhesion forces.
• To investigate the impact of varying nanostructure sizes on microbial attachment.

Main Methods:

• Utilized surface morphometry and single-cell force spectroscopy on nano-structured silicon wafers.
• Characterized surface structures using morphometric analysis based on Minkowski functionals.
• Employed hydrophobized silicon wafers etched to create structures comparable in size to bacterial cell wall molecules.

Main Results:

• Adhesion forces decrease as nanostructure size increases, correlating with the available surface area for cell wall molecule tethering.
• A bactericidal effect was observed, more pronounced on taller structures, but this did not affect adhesion.
• Morphometric analysis provided quantitative distinctions between qualitatively similar surface structures.

Conclusions:

• Results enable targeted development of 3D-structured materials to control bio-adhesion.
• The morphometric analysis methodology can serve as a gold standard for characterizing diverse material structures.
• Understanding the interplay between surface topography and microbial adhesion is crucial for designing anti-biofouling or pro-adhesion surfaces.