| Abstract
| - Energy dispersion X-ray diffraction (EDXD) was applied to investigate the structure of partly dehydratedmixed films formed by the phospholipid dimyristoyl phosphatidylcoline (DMPC) and any of the threediastereomers of the dicationic gemini surfactant (2S,3S)-2,3-dimethoxy-1,4-bis(N-hexadecyl-N,N-dimethylammonium) butane dibromide. As the surfactant to lipid molar ratio (RS/L) increases, the geminimonotonically solubilizes the lipid bilayer promoting the formation of a cubic phase of space group Pm3̄nsegregating from the residual lamellar phase of the lipid. Finally, at RS/L = 1, the phase transition iscomplete. The mixed film at the highest surfactant to lipid molar ratio (RS/L = 2.3) was hydrated by a vaporsaturated atmosphere. At full hydration, a cubic to lamellar phase transition occurs. Coarse grain dynamicinvestigations, carried out as a function of both the surfactant to lipid molar ratio and the number of watermolecules for amphiphile unit, allowed us to elucidate the structure of the emerging cubic phase and thehydration-induced structural pathway of the cubic to lamellar phase transition observed by EDXD.
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