Eur. Phys. J. E 8, 499-506 (2002)
DOI: 10.1140/epje/i2001-10108-5
Incorporating DNA in a lamellar phase: A Flory model
A. Colin and D. RouxCentre de recherche Paul-Pascal CNRS, Avenue Dr Schweitzer, 33600 Pessac, France colin@crpp.u-bordeaux.fr
(Received 16 December 2001 and Received in final form 27 June 2002 Online publication 8 October 2002)
Abstract
Following an experimental work demonstrating that DNA pieces can be
incorporated in large quantity in a neutral lamellar phase, we propose a
theoretical model showing that finite-size rod-like particles can be
incorporated in a lyotropic smectic-A phase with an interlamellar spacing
smaller than the rod length. This model based on a Flory-type description on
a lattice allowed us to calculate a ternary (rods/water/surfactant) phase
diagram. We demonstrate that a particle-enriched lamellar phase and a
particle-depleted lamellar phase can coexist. In the latter case the rods
exhibit a long-range (nematic-like) orientational order. The predictions are
in qualitative agreement with the experiments.
61.30.St - Lyotropic phases.
87.68.+z - Biomaterials and biological interfaces.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2002
