Electrically addressable, biologically relevant surface-supported bilayers

The assembly of electrically addressable, planar supported bilayers composed of biologically relevant lipids, such as those used in vesicular systems, will greatly enhance the experimental capabilities in membrane and membrane protein research. Here we assess the electrical properties of bilayers composed of a wide range of physiologically relevant lipids and lipid combinations. We demonstrate that robust, biologically relevant, planar supported bilayers with high resistance composed of 1-palmitoyl-2-oleoyl-sn- glycero-3-phosphocholine (POPC) and 25 mol % cholesterol can be constructed with high reproducibility. Furthermore, to enable studies of pore-forming peptides, which are commonly cationic, we demonstrate the construction of bilayers with biologically relevant outer leaflets incorporating up to 10 mol% negatively charged lipids. Unique features of the platform are that(1) the substrate is commercially available, atomically smooth, single-crystal silicon, (2) the polymer cushion allows for the natural incorporation of membrane proteins, and (3) the platform is highly reproducible.