In-plane correlations in a polymer-supported lipid membrane measured by off-specular neutron scattering

Polymer-supported single lipid bilayers are models to study configurations of cell membranes. We used off-specular neutron scattering to quantify in-plane height-height correlations of interfacial fluctuations of such a lipid bilayer. As temperature decreased from 37 °C to 25 °C, the polymer swells and the polymer-supported lipid membrane deviates from its initially nearly planar structure. A correlation length characteristic of capillary waves changes from 30 μm at 37 °C to 11 μm at 25 °C, while the membrane bending rigidity remains roughly constant in this temperature range.