Stripping Material from a Supported Lipid Bilayer with High Speed Buffer Flow

Abstract

A microfluidic device was created and used to demonstrate that supported lipid bilayers can be deposited on clean glass slides and removed using high velocity buffer flow (1-4 m/s linear velocity). This was accomplished by forcing the flow through a microfluidic channel covering an annealed glass coverslip bearing a supported lipid bilayer (SLB). The removal of bilayer material was monitored via fluorescence microscopy, and two basic regimes were observed: at 1-2 m/s smaller areas were stripped, while at 3-4 m/s larger areas were stripped. SLB removal was verified by two means. First, lipid vesicles labeled with a different fluorescent dye were added to the device and filled in holes left by the removal of the original SLB, allowing stripping to be verified visually. Second, the solutions obtained from stripping were concentrated and the fluorescence in the concentrates was measured. The ability to strip SLB from glass provides a relatively gentle method of creating spatially inhomogeneous SLB, which could be a useful tool in the continued investigation of membrane properties and components. KEYWORDS: Supported Lipid Bilayer; Membrane Vesicle; Microfluidic Device