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arXiv · cond-mat/0309510

Microrheology, stress fluctuations and active behavior of living cells

A. W. C. Lau·B. D. Hoffman·A. Davies·J. C. Crocker·T. C. Lubensky
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Abstract

We report the first measurements of the intrinsic strain fluctuations of living cells using a recently-developed tracer correlation technique along with a theoretical framework for interpreting such data in heterogeneous media with non-thermal driving. The fluctuations' spatial and temporal correlations indicate that the cytoskeleton can be treated as a course-grained continuum with power-law rheology, driven by a spatially random stress tensor field. Combined with recent cell rheology results, our data imply that intracellular stress fluctuations have a nearly $1/ω^2$ power spectrum, as expected for a continuum with a slowly evolving internal prestress.

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A. W. C. Lau, B. D. Hoffman, A. Davies, J. C. Crocker, T. C. Lubensky. 2003-09-22. Microrheology, stress fluctuations and active behavior of living cells. https://doi.org/10.1103/physrevlett.91.198101

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