Eur. Phys. J. E 5, 499-506 (2001)

Electrostatically induced undulations of lamellar DNA-lipid complexes

H. Schiessel¹ and H. Aranda-Espinoza<sup>2

1</sup>  Max-Planck-Institute for Polymer Research, Theory Group, PO Box 3148, 55021 Mainz, Germany
²  Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA

heli@mpip-mainz.mpg.de

(Received 2 March 2001)

Abstract
We consider DNA-cationic lipid complexes that form lamellar stacks of lipid bilayers with parallel DNA strands intercalated in between. We calculate the electrostatically induced elastic deformations of the lipid bilayers. It is found that the membranes undulate with a periodicity that is set by the DNA interaxial distance. As a consequence the lamellar repeat distance changes resulting in a swelling or compression of the lamellar stack. Such undulations may be responsible for the intermembrane coupling between DNA strands in different layers as it is observed experimentally.

PACS
68.10.-m - Fluid surfaces and fluid-fluid interfaces.
64.70.Md - Transitions in liquid crystals.


© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2001