posted on 2006-01-17, 00:00authored byMarion B. Hochrein, Christian Reich, Bärbel Krause, Joachim O. Rädler, Bert Nickel
Supported lipid membranes constitute one of the most important model systems for cell membranes. The properties
of lipid membranes supported by the hydrophobic solid polymer cyclic olefin copolymer (COC) were investigated.
Lipid layers consisting of varying amounts of 1,2-dioleoyl-3-trimethylammonium propane (DOTAP, cationic) and
1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC, neutral) prepared by vesicle fusion and solvent exchange were
compared. All lipid mixtures coated the COC surface homogeneously forming a fluid membrane as verified by
fluorescence microscopy and fluorescence recovery after photobleaching (FRAP). The exact structure of the supported
membranes was determined by synchrotron reflectivity experiments using a microfluidic chamber. The X-ray data
are in agreement with a compressed (head-to-head distance = 29 Å) and less densely packed bilayer.