Lipid mobility and molecular binding in fluid lipid membranes.

The lateral mobility of dilute concentrations of fluorescently labeled lipids doped into supported membranes is found to change upon receptor ligand binding at the membrane surface, even when the lipid is not directly involved in the binding event. Experiments using membrane microarrays are performed that illustrate the use of lipid mobility measurements as an effectively label-free strategy of detecting binding on membrane surfaces.