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DNA Nanotubes as a Versatile Tool to Study Semiflexible Polymers
Published on: October 25, 2017
Ratchet nanofiltration of DNA
Joel D P Thomas1, Mark N Joswiak, Daniel W Olson
1Department of Chemical Engineering and Materials Science, University of Minnesota - Twin Cities, 421 Washington Ave SE, Minneapolis, MN 55455, USA.
Abstract:
The DNA nanofilter is a microfabricated electrophoretic separation device consisting of a periodic array of thin slits (circa 60 nm) separated by deeper wells (circa 320 nm). We demonstrate that this device can act as a tuneable, clog-free filter when operating in a low frequency, asymmetric field inversion mode. This filtration occurs by using asymmetric field inversion to achieve bi-directional migration of short (less than 1000 bp) DNA. Moreover, similar ratchet-type operation can improve separations when compared to a constant field separation in the same device. These modes of operation enhance the utility of the DNA nanofilter as a component of integrated lab-on-a-chip devices. The experimental data confirm theoretical predictions for the bidirectional transport of DNA in entropy-based separations.

