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arXiv · 1004.4764

Differential Dynamic Microscopy of Bacterial Motility

Laurence G. Wilson·Vincent A. Martinez·Jana Schwarz-Linek·J. Tailleur·Peter N. Pusey·Gary Bryant·Wilson C. K. Poon
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Abstract

We demonstrate 'differential dynamic microscopy' (DDM) for the fast, high throughput characterization of the dynamics of active particles. Specifically, we characterize the swimming speed distribution and the fraction of motile cells in suspensions of Escherichia coli bacteria. By averaging over ~10^4 cells, our results are highly accurate compared to conventional tracking. The diffusivity of non-motile cells is enhanced by an amount proportional to the concentration of motile cells.

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Laurence G. Wilson, Vincent A. Martinez, Jana Schwarz-Linek, J. Tailleur, Peter N. Pusey, Gary Bryant, Wilson C. K. Poon. 2010-10-02. Differential Dynamic Microscopy of Bacterial Motility. https://doi.org/10.1103/physrevlett.106.018101

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