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arXiv · 2009.07081

CO$_2$-driven diffusiophoresis for removal of bacteria

Suin Shim·Sepideh Khodaparast·Ching-Yao Lai·Jing Yan·Jesse T. Ault·Bhargav Rallabandi·Orest Shardt·Howard A. Stone
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Abstract

We investigate CO$_2$-driven diffusiophoresis of colloidal particles and bacterial cells in a Hele-Shaw geometry. Combining experiments and a model, we understand the characteristic length and time scales of CO$_2$-driven diffusiophoresis in relation to system dimensions and CO$_2$ diffusivity. Directional migration of wild-type V. cholerae and a mutant lacking flagella, as well as S. aureus and P. aeruginosa, near a dissolving CO$_2$ source shows that diffusiophoresis of bacteria is achieved independent of cell shape and Gram stain. Long-time experiments suggest possible applications for bacterial diffusiophoresis to cleaning systems or anti-biofouling surfaces.

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Suin Shim, Sepideh Khodaparast, Ching-Yao Lai, Jing Yan, Jesse T. Ault, Bhargav Rallabandi, Orest Shardt, Howard A. Stone. 2020-09-14. CO$_2$-driven diffusiophoresis for removal of bacteria. https://arxiv.org/abs/2009.07081

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