On the Formation of Lipid Nano-Scale Structures at Interfaces Beyond Planar Bilayers

Abstract

Biological membranes do not only occur as planar bilayer structures, but bilayers have also been shown to, depending on the lipid composition, curve into intriguing 3D structures. Understanding the biological implication as well as the application of such interfaces, for e.g. drug delivery and other biomedical application, requires the development of well-defined model system.Here we demonstrate the formation of fluid supported bilayers on vertical gallium phosphide nanowire (NW) forests using self-assembly from lipid vesicular dispersions (1-2). The phospholipid mixture used had a composition that facilitates the formation of curved bilayers. By applying fluorescence recovery after photobleaching, we determined that the lipids are able to diffuse laterally within the NW-supported bilayer and that the bilayers were found to follow the contours of the nanowires to form continuous and locally highly curved model membranes. Membrane-anchoring proteins as well as tethered vesicles were found to be able to bind to these bilayers on the nanowire substrate.(1) Dabkowska, A.P., Niman, C.S., Piret, G., Persson, H., Wacklin, H.P., Linke, H., Prinz, C.N. & Nylander, T. Fluid and highly curved model membranes on vertical nanowire arrays. Nano Letters, 2014, 14, 4286-4292.(2) Dabkowska, A. P., Piret, G., Niman, C. S., Lard, M., Linke, H., Nylander, T., Prinz, C., N.: Surface nanostructures for fluorescence probing of supported lipid bilayers on reflective substrates. 2015, Accepted in Nanoscale