title: Supported membranes embedded with fixed arrays of gold nanoparticles.
abstract: We present a supported membrane platform consisting of a fluid lipid bilayer membrane embedded with a fixed array of gold nanoparticles. The system is realized by preforming a hexagonal array of gold nanoparticles (∼5-7 nm) with controlled spacing (∼50-150 nm) fixed to a silica or glass substrate by block copolymer lithography. Subsequently, a supported membrane is assembled over the intervening bare substrate. Proteins or other ligands can be associated with the fluid lipid component, the fixed nanoparticle component, or both, providing a hybrid interface consisting of mobile and immobile components with controlled geometry. We test different biochemical coupling strategies to bind individual proteins to the particles surrounded by a fluid lipid membrane. The coupling efficiency to nanoparticles and the influence of nanoparticle arrays on the surrounding membrane integrity are characterized by fluorescence imaging, correlation spectroscopy, and super-resolution fluorescence microscopy. Finally, the functionality of this system for live cell experiments is tested using the ephrin-A1-EphA2 juxtacrine signaling interaction in human breast epithelial cells.
authors.affiliation: Howard Hughes Medical Institute and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States.
authors.forename: Theobald
authors.initials: T
authors.lastname: Lohmüller
authors.forename: Sara
authors.initials: S
authors.lastname: Triffo
authors.forename: Geoff P
authors.initials: GP
authors.lastname: O'Donoghue
authors.forename: Qian
authors.initials: Q
authors.lastname: Xu
authors.forename: Michael P
authors.initials: MP
authors.lastname: Coyle
authors.forename: Jay T
authors.initials: JT
authors.lastname: Groves
mesh_terms: D003460:Crystallization / Q000379:methods; D006046:Gold / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008565:Membrane Proteins / Q000737:chemistry*; D008567:Membranes, Artificial; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D008051:Lipid Bilayers; D046911:Macromolecular Substances; D008565:Membrane Proteins; D008567:Membranes, Artificial; D006046:Gold