Visualizing the strain field in semiflexible polymer networks: strain fluctuations and nonlinear rheology of F-actin gels.
We image semiflexible polymer networks under shear at the micrometer scale. By tracking embedded probe particles, we determine the local strain field, and directly measure its uniformity, or degree of affineness, on scales of 2-100 microm. The degree of nonaffine strain depends upon the polymer length and cross-link density, consistent with theoretical predictions. We also find a direct correspondence between the uniformity of the microscale strain and the nonlinear elasticity of the networks in the bulk.
Department of Physics & SEAS, Harvard University, Cambridge, MA 02138, USA.
J
J
Liu
G H
GH
Koenderink
K E
KE
Kasza
F C
FC
Mackintosh
D A
DA
Weitz
D000199:Actins / Q000737:chemistry*; D000818:Animals; D001696:Biomechanical Phenomena; D003432:Cross-Linking Reagents / Q000737:chemistry; D005782:Gels / Q000737:chemistry; D006737:Horseshoe Crabs / Q000737:chemistry; D008297:Male; D017711:Nonlinear Dynamics; D012212:Rheology; D033081:Shear Strength; D013094:Spermatozoa / Q000737:chemistry
D000199:Actins; D003432:Cross-Linking Reagents; D005782:Gels; C083765:scruin protein, Horseshoe Crab