Direct measurement of the intermolecular forces confining a single molecule in an entangled polymer solution
Soft Condensed Matter
2009-11-13 v1
Abstract
We use optical tweezers to directly measure the intermolecular forces acting on a single polymer imposed by surrounding entangled polymers (115 kbp DNA, 1 mg/ml). A tube-like confining field was measured in accord with the key assumption of reptation models. A time-dependent harmonic potential opposed transverse displacement, in accord with recent simulation findings. A tube radius of 0.8 microns was determined, close to the predicted value (0.5 microns). Three relaxation modes (~0.4, 5 and 30 s) were measured following transverse displacement, consistent with predicted relaxation mechanisms.
Cite
@article{arxiv.0706.3414,
title = {Direct measurement of the intermolecular forces confining a single molecule in an entangled polymer solution},
author = {Rae M. Robertson and Douglas E. Smith},
journal= {arXiv preprint arXiv:0706.3414},
year = {2009}
}