Role of Surface Properties in Initial Attachment of Bacteria

Bacterial biofilms foul a wide range of engineered surfaces, from pipelines to membranes to biomedical implants, and lead to deleterious costs for industry and for human health. Designing strategies to reduce bacterial fouling requires fundamental understanding of mechanisms by which bacteria attach to surfaces. We investigate the attachment of Escherichia coli on silanized glass surfaces during flow through a linear channel at flow rates of 0.1—1 mL/min using confocal microscopy. We deposit self-assembled monolayers of organosilanes on glass and track the position and orientation of bacteria deposited on these surfaces during flow using high-throughput image processing algorithms. Here, we report the rate of deposition, surface-tethered motion, and irreversible adhesion of bacteria on surfaces of different charge and energy. We find that a metric based on the amount of short-time motion of bacteria that is driven by flagella is linearly correlated with deposition rate, whereas conventional surface characterizations such as surface energy or water contact angle are uncorrelated. Our results suggest that attachment of bacteria on these engineered surfaces is dominated by different physical mechanisms.