Document Type
Article
Publication Date
7-2007
Department 1
Physics
Abstract
Can nonspecifically bound divalent counterions induce attraction between DNA strands? Here, we present experimental evidence demonstrating attraction between short DNA strands mediated by Mg2 ions. Solution small angle x-ray scattering data collected as a function of DNA concentration enable model independent extraction of the second virial coefficient. As the [Mg2] increases, this coefficient turns from positive to negative reflecting the transition from repulsive to attractive inter-DNA interaction. This surprising observation is corroborated by independent light scattering experiments. The dependence of the observed attraction on experimental parameters including DNA length provides valuable clues to its origin.
Copyright Note
This is the publisher's version of the work. This publication appears in Gettysburg College's institutional repository by permission of the copyright owner for personal use, not for redistribution.
Recommended Citation
Qiu, X., Andresen, K., Kwok, L.W., Lamb, J.S., Park, H.Y., & Pollack, L. (2007). Inter-DNA attraction mediated by divalent counterions. Physical Review Letters,99(038104). http://dx.doi.org/10.1103/PhysRevLett.99.038104
Required Publisher's Statement
© 2007 The American Physical Society