Confinement of Fluorescent Probes in Microwells on Si Substrates by Sealing with Lipid Bilayers

We investigated the optimum architecture for confining fluorescent probes in microwells on a Si substrate by covering it with a lipid bilayer. We modified the structure of the wells to prevent the lipid membrane from falling into them, and the overhang shape at the aperture improved the probability of confinement. The fluorescence intensity from the calcein confined in the wells remained unchanged for one hour or more, indicating that the probes remain stably in the wells without flowing out. An artificial cell sealed with the suspended membrane is a promising tool for the functional analysis of membrane proteins. (C) 2010 The Japan Society of Applied Physics