Structure of solid-supported lipid–DNA–metal complexes investigated by energy dispersive X-ray diffraction

When mixing aqueous solutions of DNA and dioloeyl-phosphatidylcholine multilamellar liposomes in the presence of Mn2+ ions, a multilamellar liquid-crystalline phase is formed in which DNA monolayers are comprised between opposing lipid bilayers. Here, we report on a new experimental procedure resulting in the formation of solid-supported DOPC–DNA–Mn2+ complexes in the biologically relevant excess water condition. The supramolecular structure of solid-supported complexes, characterized by means of Energy Dispersive X-ray Diffraction, exhibits very similar structural properties with respect to the solution structure of the complexes as revealed by synchrotron Small Angle X-ray Scattering measurements.