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arXiv · 1006.1445

Instabilities and Oscillations in Isotropic Active Gels

Shiladitya Banerjee·M. Cristina Marchetti
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Abstract

We present a generic formulation of the continuum elasticity of an isotropic crosslinked active gel. The gel is described by a two-component model consisting of an elastic network coupled frictionally to a permeating fluid. Activity is induced by active crosslinkers that undergo an ATP-activated cycle and transmit forces to the network. The on/off dynamics of the active crosslinkers is described via rate equations for unbound and bound motors. For large activity motors yield a contractile instability of the network. At smaller values of activity, the on/off motor dynamics provides an effective inertial drag on the network that opposes elastic restoring forces, resulting in spontaneous oscillations. Our work provides a continuum formulation that unifies earlier microscopic models of oscillations in muscle sarcomeres and a generic framework for the description of the large scale properties of isotropic active solids.

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Shiladitya Banerjee, M. Cristina Marchetti. 2010-10-04. Instabilities and Oscillations in Isotropic Active Gels. https://doi.org/10.1039/c0sm00494d

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