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arXiv · 2112.05266

Mass changes the diffusion coefficient of particles with ligand-receptor contacts in the overdamped limit

Sophie Marbach·Miranda Holmes-Cerfon
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Abstract

Inertia does not generally affect the long-time diffusion of passive overdamped particles in fluids. Yet a model starting from the Langevin equation predicts a surprising property of particles coated with ligands, that bind reversibly to surface receptors -- heavy particles diffuse more slowly than light ones of the same size. We show this by simulation and by deriving an analytic formula for the mass-dependent diffusion coefficient in the overdamped limit. We estimate the magnitude of this effect for a range of biophysical ligand-receptor systems, and find it is potentially observable for tailored micronscale DNA-coated colloids.

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Sophie Marbach, Miranda Holmes-Cerfon. 2021-12-10. Mass changes the diffusion coefficient of particles with ligand-receptor contacts in the overdamped limit. https://doi.org/10.1103/physrevlett.129.048003

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