Speaker
Bernhard Mehlig
(Gothenburg University)
Description
The extension of DNA during confinement in a nanochannel has
attracted substantial attention for next-generation genomics
and as a fundamental problem in polymer physics. But recent
experiments measuring DNA extension in nanonchannels are at
odds with even the most basic predictions of current scaling
theories for the conformations of confined semiflexible
polymers like DNA. We posit that this discrepancy arises
because the experimental systems do not satisfy the strong
inequalities underlying the existing scaling theory. We
develop a new theory, based on the properties of a weakly
self-avoiding, one-dimensional random walk. Both recent
experimental results and new simulation data reported here
collapse onto one master curve as a function of a single
parameter that varies continuously throughout the
experimentally relevant region of the parameter space. In
special cases previous scaling theories are recovered.
