| Abstract
| - The ability to manipulate supported lipid bilayers after formation on a substrate has made possible newclasses of both molecular and cellular level experiments. In this report, we combine the unique propertiesof these lipid systems with laminar flow concepts to selectively remove, collect, and reconstitute lipidbilayers from specified regions of a surface. A stream of detergent solution was directed over a preformedbilayer, resulting in the removal of bilayer material; mixing between adjacent flows at low Reynoldsnumber is diffusion limited, providing confinement of this stripping solution and, consequently, bilayerremoval with precision on the order of several micrometers. The freshly exposed surface allows formationof new connected bilayer when exposed to lipid vesicles. In conjunction with surface micropatterning andelectrophoretic manipulation, we further demonstrate a first-generation, membrane-based separation/purification strategy. Flow-based manipulation of lipid bilayers forms the basis of biomembrane microfluidics.In particular, the directed introduction of lipids or other materials provides a route toward dynamic formationand erasure of barriers to lipid diffusion. As examples of future applications of these methods, we discussthe separation of mobile from immobile membrane components and a route toward spatially resolvedlabel-free analysis of composition gradients in patterned supported membranes.
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