Structural Characterisation of Nanoparticle-Supported Lipid Bilayers by Grazing Incidence X-ray and Neutron Scattering

Abstract

The structure of supported lipid bilayers formed on a monolayer of nanoparticles was determined using a combination of grazing incidence X-ray and neutron scattering techniques. Ordered nanoparticle arrays assembled on a silicon crystal using a Langmuir-Schaefer deposition were shown to be suitable and stable substrates for the formation of curved and fluid lipid bilayers that retained lateral mobility, as shown by fluorescence recovery after photobleaching. A comparison between the structure of the curved bilayer assembled around the nanoparticles with the planar lipid membrane formed on the flat underlying silicon oxide surface revealed a [~]5 [A] thinner bilayer on the curved interface, resolving the effects of curvature on the lipid packing and overall bilayer structure. The combination of neutron scattering techniques, which grant access to sub-nanometre scale structural information at buried interfaces, and nanoparticle-supported lipid bilayers, offers a novel approach to investigate the effects of membrane curvature on lipid bilayers.