It is Easier for a Camel to Pass Through the Eye of a Needle: Driving Polymer Translocation Through a Nanopore Using Various Asymmetries

When: Thursday, February 13, 2014 at 4:00 pm
Where: DA 114
Speaker: Professor Gary Slater
Organization: Department of Physics, Faculty of Science, University of Ottawa
Sponsor: Physics Colloquium

Polymer translocation is relevant both in vivo and for nanotechnology applications. Not surprisingly, this apparently simple process has thus been the subject of intense (experimental, theoretical and numerical) study. For instance, there have been numerous simulation studies examining aspects of both biased and unbiased translocation. In the first part of this talk, I will review our results for unbiased translocation, and I will focus on the fact that there appears to be no experimentally relevant scaling exponent. I will then present results for translocation driven by unusual system asymmetries (or chemical potential gradients). First, I will consider the case of a gradient of solvent viscosity across the membrane: can this drive the translocation, and if so, towards which side? For the second example, I will consider translocation when different obstacle arrangements are present on both sides of the pore. Interestingly, we find that even when the concentration of obstacles is uniform, varying arrangement of the obstacles can yield a preferential direction.

Host: Assistant Professor Meni Wanunu