Relationship between Structure and Fluctuations of Lipid Nonlamellar Phases Deposited at the Solid–Liquid Interface

• DOI: 10.1021/acs.jpcb.6b11038
• Publication Date: 2017-03-07T15:07:59Z
• Authors: Tommy Nylander; Olaf Soltwedel; Marina Ganeva; Christopher Hirst; James Holdaway; Marianna Yanez Ar...; Maria Wadsäter; Justas Barauskas; Henrich Frielinghaus; Olaf Holderer
• Keywords: 02 engineering and technology; info:eu-repo/classification/ddc/530; 0210 nano-technology

The structure and dynamics of nanostructure films formed by mixtures of soy phosphatidylcholine and glycerol dioleate at the silicon-aqueous interface were studied by grazing incidence neutron spin echo spectroscopy (GINSES), specular and off-specular neutron reflectometry, and small-angle X-ray diffraction. Reverse hexagonal (HII) and micellar cubic phase (Fd3m) layers at the solid-liquid interface have been identified with neutron reflectometry measurements. A preferred orientation of the liquid crystalline (LC) domains was observed only for the anisotropic HII phase. The size of the LC domains was found to be about 1 micrometer as estimated from the width of the diffraction peaks. GINSES revealed that the cubic phase forms rather rigid films. In comparison, the HII film was more flexible, appearing as a modified undulation spectrum of the cylinders due to the interaction with the substrate.