Departmental Papers (CBE)

Document Type

Journal Article

Date of this Version

October 2003


Copyright American Physical Society. Reprinted from Physical Review Letters, Volume 91, Issue 15, Article 158302, October 2003, 4 pages.
Publisher URL:


We measure the viscoelasticity of entangled F-actin over length scales between 1 and 100 µm using one- and two-particle microrheology, and directly identify two distinct microscopic contributions to the elasticity. Filament entanglements lead to a frequency-independent elastic modulus over an extended frequency range of 0:01–30 rad/ sec; this is probed with one-particle microrheology. Longitudinal fluctuations of the filaments increase the elastic modulus between 0.1 and 30 rad/ sec at length scales up to the filament persistence length; this is probed by two-particle microrheology.



Date Posted: 20 December 2005

This document has been peer reviewed.