Dresden 2017 – wissenschaftliches Programm
BP 21.7: Poster
Dienstag, 21. März 2017, 14:00–16:00, P1A
Element-specific Density Profiles in Single and Interacting Solid-supported Biomembrane Models — •Georgi Gochev1,2, Ernesto Scoppola1, Ignacio Rodriguez-Loureiro1, Luca Bertinetti1, Dmitri Novikov3, Oleg Konovalov4, Philippe Fontaine5, and Emanuel Schneck1 — 1Max Planck Institute Colloids and Interfaces, Potsdam, Germany — 2Institute of Physical Chemistry, Sofia, Bulgaria — 3Deutsches Elektronen-Synchrotron, Hamburg, Germany — 4European Synchrotron Radiation Facility, Grenoble, France — 5Synchrotron SOLEIL, Gif-sur-Yvette, France
Surface interactions involving biomembranes, such as cell-cell interactions or membrane contacts inside cells play important roles in numerous biological processes. Structural insight into the interacting surfaces is a prerequisite to understand the interaction characteristics as well as the underlying physical mechanisms. Here, we work with simplified planar experimental models of membrane surfaces, composed of lipids and lipopolymers. Their interaction is quantified in terms of pressure-distance curves using ellipsometry at controlled dehydrating (interaction) pressures. For selected pressures, their internal structure is investigated by standing-wave x-ray fluorescence (SWXF). This technique yields specific density profiles of the chemical elements P and S belonging to lipid headgroups and polymer chains, as well as counter-ion profiles for charged surfaces. Along this line we further establish methodology for the element-specific structural characterization of lipid monolayers at the solid/liquid interface with atom-scale resolution.