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arXiv · 1105.6338

3D rotational diffusion microrheology using 2D video microscopy

Rémy Colin·Minhao Yan·Loudjy Chevry·Jean-François Berret·Bérengère Abou
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Abstract

We propose a simple way to perform three-dimensional (3D) rotational microrheology using two-dimensional (2D) video microscopy. The 3D rotational brownian motion of micrometric wires in a viscous fluid is deduced from their projection on the focal plane of an optical microscope objective. The rotational diffusion coefficient of the wires of length between 1-100 μm is extracted, as well as their diameter distribution in good agreement with electron microscopy measurements. This is a promising way to characterize soft visco-elastic materials, and probe the dimensions of anisotropic objects.

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Rémy Colin, Minhao Yan, Loudjy Chevry, Jean-François Berret, Bérengère Abou. 2012-01-05. 3D rotational diffusion microrheology using 2D video microscopy. https://doi.org/10.1209/0295-5075%2F97%2F30008

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