Evidence of an inverted hexagonal phase in self-assembled phospholipid-DNA-metal complexes

Abstract

We report the first observation of an inverted hexagonal phase of phospholipid-
\nDNA-metal complexes. These ternary complexes are formed in a self-assembled manner when
\nwater solutions of neutral lipid dioleoylphosphatidylethanolamine (DOPE), DNA and divalent
\nmetal cations (Me2+; Me = Fe, Co, Mg, Mn) are mixed, which represents a striking example
\nof supramolecular chemistry. The structure, derived from synchrotron X-ray diffraction,
\nconsists of cylindrical DNA strands coated by neutral lipid monolayers and arranged on a
\ntwo-dimensional hexagonal lattice (Hc
\nII ). Besides the fundamental aspects, DOPE-DNA-Me2+
\ncomplexes may be of great interest as efficient nonviral delivery systems in gene therapy applications
\nbecause of the low inherent cytotoxicity and the potential high transfection efficiency.