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TT: Fachverband Tiefe Temperaturen
TT 23: Transport: Nanoelectronics III - Molecular Electronics
TT 23.4: Vortrag
Mittwoch, 25. März 2009, 10:15–10:30, HSZ 105
Screw motion of a DNA duplex during translocation through a nanopore: A coarse-grained model — •Rafael Gutierrez1, Jewgeni Starikov2, Dirk Hennig3, Hiroaki Yamada4, Gianaurelio Cuniberti1, and Bengt Norden5 — 1Institute for Materials Science, Dresden University of Technology, D-01062 Dresden, Germany — 2Institute for Theoretical Solid State Physics, University of Karlsruhe, D-76131 Karlsruhe, Germany — 3Institute for Physics, Humboldt University of Berlin, D-12489 Berlin, Germany — 4Yamada Physics Research Laboratory, Niigata 950-2002, Japan — 5Department of Physical Chemistry, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden
Based upon the structural properties of DNA and their counterion-water surrounding in solution, we have introduced a screw model describing DNA translocation through artificial nanopores in a qualitatively correct way.[1] This model represents DNA as a "screw", whereas the counterion-hydration shell is a "nut". When an electrical potential is applied across a membrane with a nanopore, the "screw" and "nut" begin to move with respect to each other, so that their mutual rotation is coupled with their mutual translation. As a result, there are peaks of electrical current connected with the mutual translocation of DNA and its counterion-hydration shell, if DNA has some non-regular base-pair sequence. The calculated peaks of current strongly resemble those observed in the pertinent experiments.
[1] E. B. Starikov, D. Hennig, H. Yamada, R. Gutierrez, G. Cuniberti, and B. Norden, submitted (2008)