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arXiv · 0806.2898

Hydrodynamic attraction of swimming microorganisms by surfaces

Allison P. Berke·Linda Turner·Howard C. Berg·Eric Lauga
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Abstract

Cells swimming in confined environments are attracted by surfaces. We measure the steady-state distribution of smooth-swimming bacteria (Escherichia coli) between two glass plates. In agreement with earlier studies, we find a strong increase of the cell concentration at the boundaries. We demonstrate theoretically that hydrodynamic interactions of the swimming cells with solid surfaces lead to their re-orientation in the direction parallel to the surfaces, as well as their attraction by the closest wall. A model is derived for the steady-state distribution of swimming cells, which compares favorably with our measurements. We exploit our data to estimate the flagellar propulsive force in swimming E. coli.

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Allison P. Berke, Linda Turner, Howard C. Berg, Eric Lauga. 2008-06-18. Hydrodynamic attraction of swimming microorganisms by surfaces. https://doi.org/10.1103/physrevlett.101.038102

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