title: Nanoscale phase behavior on flat and curved membranes.
abstract: The diverse physical properties of membranes play a critical role in many membrane associated biological processes. Proteins responsible for membrane transport can be affected by the lateral membrane order and lateral segregation of proteins is often controlled by the preference of certain membrane anchors for membrane phases having a physically ordered state. The dynamic properties of coexisting membrane phases are often studied by investigating their thermal behavior. Optical trapping of gold nanoparticles is a useful tool to generate local phase transitions in membranes. The high local temperatures surrounding an irradiated gold nanoparticle can be used to melt a part of a giant unilamellar lipid vesicle (GUV) which is then imaged using phase sensitive fluorophores embedded within the bilayer. By local melting of GUVs we reveal how a protein-free, one component lipid bilayer can mediate passive transport of fluorescent molecules by localized and transient pore formation. Also, we show how tubular membrane curvatures can be generated by optical pulling from the melted region on the GUV. This will allow us to measure the effect of membrane curvature on the phase transition temperature.
authors.affiliation: Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Andersen
authors.forename: Azra
authors.initials: A
authors.lastname: Bahadori
authors.forename: Dino
authors.initials: D
authors.lastname: Ott
authors.forename: Anders
authors.initials: A
authors.lastname: Kyrsting
authors.forename: S Nader S
authors.initials: SN
authors.lastname: Reihani
authors.forename: Poul M
authors.initials: PM
authors.lastname: Bendix
mesh_terms: D005456:Fluorescent Dyes; D006046:Gold / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D053768:Metal Nanoparticles; D010713:Phosphatidylcholines / Q000737:chemistry; D053835:Unilamellar Liposomes / Q000737:chemistry
chemical_list: D005456:Fluorescent Dyes; D008051:Lipid Bilayers; D010713:Phosphatidylcholines; D053835:Unilamellar Liposomes; D006046:Gold; C037108:1,2-pentadecanoylphosphatidylcholine