title: Collapse of DNA in ac electric fields.
abstract: We report that double-stranded DNA collapses in the presence of ac electric fields at frequencies of a few hundred Hertz, and does not stretch as commonly assumed. In particular, we show that confinement-stretched DNA can collapse to about one quarter of its equilibrium length. We propose that this effect is based on finite relaxation times of the counterion cloud, and the subsequent partitioning of the molecule into mutually attractive units. We discuss alternative models of those attractive units.
authors.affiliation: North Carolina State University, Department of Physics, Raleigh, North Carolina 27695, USA.
authors.forename: Chunda
authors.initials: C
authors.lastname: Zhou
authors.forename: Walter W
authors.initials: WW
authors.lastname: Reisner
authors.forename: Rory J
authors.initials: RJ
authors.lastname: Staunton
authors.forename: Amir
authors.initials: A
authors.lastname: Ashan
authors.forename: Robert H
authors.initials: RH
authors.lastname: Austin
authors.forename: Robert
authors.initials: R
authors.lastname: Riehn
mesh_terms: D004247:DNA / Q000737:chemistry*; D004560:Electricity; D044085:Microfluidics; D008958:Models, Molecular
chemical_list: D004247:DNA