title: Rupture pathway of phosphatidylcholine liposomes on silicon dioxide.
abstract: We have investigated the pathway by which unilamellar POPC liposomes upon adsorption undergo rupture and form a supported lipid bilayer (SLB) on a SiO(2) surface. Biotinylated lipids were selectively incorporated in the outer monolayer of POPC liposomes to create liposomes with asymmetric lipid compositions in the outer and inner leaflets. The specific binding of neutravidin and anti-biotin to SLBs formed by liposome fusion, prior to and after equilibrated flip-flop between the upper and lower monolayers in the SLB, were then investigated. It was concluded that the lipids in the outer monolayer of the vesicle predominantly end up on the SLB side facing the SiO(2) substrate, as demonstrated by having maximum 30-40% of lipids in the liposome outer monolayer orienting towards the bulk after forming the SLB.
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.|Laboratory for Surface Science and Technology, Department of Materials, Swiss Federal Institute of Technology Zurich (ETH Zurich), CH-8093 Zurich, Switzerland.
authors.forename: Erik
authors.initials: E
authors.lastname: Reimhult
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.|Laboratory for Surface Science and Technology, Department of Materials, Swiss Federal Institute of Technology Zurich (ETH Zurich), CH-8093 Zurich, Switzerland.
authors.forename: Bengt
authors.initials: B
authors.lastname: Kasemo
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Höök
mesh_terms: D019921:Biotinylation; D008081:Liposomes / Q000737:chemistry*; D010713:Phosphatidylcholines / Q000737:chemistry; D058525:Quartz Crystal Microbalance Techniques; D012822:Silicon Dioxide / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D008081:Liposomes; D010713:Phosphatidylcholines; D012822:Silicon Dioxide