Evidence of an inverted hexagonal phase in self-assembled phospholipid- -metal complexesO. Francescangeli1, M. Pisani2, V. Stanic1, P. Bruni2 and T. M. Weiss3
1 Dipartimento di Fisica e Ingegneria dei Materiali e del Territorio and INFM Università Politecnica delle Marche - Via Brecce Bianche, 60131 Ancona, Italy
2 Dipartimento di Scienze dei Materiali e della Terra, Università Politecnica delle Marche - Via Brecce Bianche, 60131 Ancona, Italy
3 European Synchrotron Radiation Facility - BP 220, F-38043 Grenoble Cedex, France
(Received 27 April 2004; accepted in final form 7 June 2004)
We report the first observation of an inverted hexagonal phase of phospholipid-DNA-metal complexes. These ternary complexes are formed in a self-assembled manner when water solutions of neutral lipid dioleoylphosphatidylethanolamine (DOPE), DNA and divalent metal cations ( ; , , , ) are mixed, which represents a striking example of supramolecular chemistry. The structure, derived from synchrotron X-ray diffraction, consists of cylindrical DNA strands coated by neutral lipid monolayers and arranged on a two-dimensional hexagonal lattice ( HIIc). Besides the fundamental aspects, DOPE-DNA- complexes may be of great interest as efficient nonviral delivery systems in gene therapy applications because of the low inherent cytotoxicity and the potential high transfection efficiency.
87.14.Cc - Lipids.
87.14.Gg - DNA, RNA.
61.10.-i - X-ray diffraction and scattering.
© EDP Sciences 2004