A shear-induced limit on bacterial surface adhesion in fluid flow

Journal article

Controlling bacterial surface adhesion and subsequent biofilm formation in fluidsystems is crucial for the safety and efficacy of medical and industrial processes. Here,we theoretically examine the transport of bacteria close to surfaces, isolating how thekey processes of bacterial motility and fluid flow interact and alter surface adhesion.We exploit the disparity between the fluid velocity and the swimming velocity ofcommon motile bacteria and, using a hybrid asymptotic-computational approach,we systematically derive the coarse-grained bacterial diffusivity close to surfaces asa function of swimming speed, rotational diffusivity, and shape. We calculate ananalytical upper bound for the bacterial adhesion rate by considering the scenario inwhich bacteria adhere irreversibly to the surface on first contact. Our theory predictsthat maximal adhesion occurs at intermediate flow rates: At lower flow rates, increasingflow increases surface adhesion, while at higher flow rates, adhesion is decreased byshear-induced cell reorientation.

Authors: Yeo, E; Walker, B; Pearce, P; Dalwadi, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: National Academy of Sciences
• Journal: Proceedings of the National Academy of Sciences
• Volume: 123
• Issue: 4
• Article number: e2516069123
• Publication date: 2026-01-21
• Acceptance date: 2025-12-11
• DOI: 10.1073/pnas.2516069123
• EISSN: 1091-6490
• ISSN: 0027-8424
• Language: English
• Keywords: bacterial adhesion; active flow; biofilm formation