Formation of pit-spanning phospholipid bilayers on nanostructured silicon dioxide surfaces for studying biological...

Zwitterionic phospholipid vesicles are known to adsorb and ultimately rupture on flat silicon dioxide (SiO2) surfaces to form supported lipid bilayers. Surface topography, however, alters the kinetics and mechanistic details of vesicles adsorption, which under certain conditions may be exploited to form a suspended bilayer. Here we describe the use of nanostructured SiO2 surfaces prepared by the colloidal lithography technique to scrutinize the formation of suspended 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid bilayers from a solution of small unilamellar lipid vesicles (SUVs). Atomic force microscopy (AFM) and quartz crystal microbalance with dissipation monitoring (QCM-D) were employed to characterize nanostructure fabrication and lipid bilayer assembly on the surface.