Nanofluidics in cellular tubes under oscillatory extension

¹  Physico-Chimie Curie, Institut Curie, Section de Recherche - 26 rue d'Ulm, 75248 Paris Cedex 05, France, EU
²  Department of Physics and Astronomy, The University of California at Los Angeles Los Angeles 90095-1569, CA, USA

Corresponding authors: pierre.nassoy@curie.fr francoise.brochard@curie.fr

Received: 5 June 2008
Accepted: 22 August 2008

Abstract

Membrane nanotubes or tethers extruded from cells exhibit dynamic features that are believed to exhibit viscoelastic rheological properties. We have performed typical microrheology experiments on tethers pulled from red blood cells by measuring the force response to small oscillatory extensions or compressions. Our data, supported by a simple theoretical model, show that the force response does not reflect any intrinsic viscoelastic properties of the tethers themselves, but instead is dominated by the drainage of the internal cellular fluid into and out of the oscillating nanoconduit over a frequency-dependent penetration depth. The simplicity of tether rheology suggests its usage as a probe for measuring the local viscosity of the cytosol near the plasma membrane.