title: Direct observation and control of supported lipid bilayer formation with interferometric scattering microscopy.
abstract: Supported lipid bilayers (SLB) are frequently used to study processes associated with or mediated by lipid membranes. The mechanism by which SLBs form is a matter of debate, largely due to the experimental difficulty associated with observing the adsorption and rupture of individual vesicles. Here, we used interferometric scattering microscopy (iSCAT) to directly visualize membrane formation from nanoscopic vesicles in real time. We observed a number of previously proposed phenomena such as vesicle adsorption, rupture, movement, and a wave-like bilayer spreading. By varying the vesicle size and the lipid-surface interaction strength, we rationalized and tuned the relative contributions of these phenomena to bilayer formation. Our results support a model where the interplay between bilayer edge tension and the overall interaction energy with the surface determine the mechanism of SLB formation. The unique combination of sensitivity, speed, and label-free imaging capability of iSCAT provides exciting prospects not only for investigations of SLB formation, but also for studies of assembly and disassembly processes on the nanoscale with previously unattainable accuracy and sensitivity.
authors.affiliation: Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford , South Parks Road, Oxford OX1 3QZ, United Kingdom .
authors.forename: Joanna
authors.initials: J
authors.lastname: Andrecka
authors.forename: Katelyn M
authors.initials: KM
authors.lastname: Spillane
authors.forename: Jaime
authors.initials: J
authors.lastname: Ortega-Arroyo
authors.forename: Philipp
authors.initials: P
authors.lastname: Kukura
mesh_terms: D000327:Adsorption; D004058:Diffusion; D005898:Glass; D007368:Interferometry / Q000379:methods*; D008027:Light; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry; D008853:Microscopy; D036103:Nanotechnology; D055095:Optics and Photonics; D010316:Particle Size; D010713:Phosphatidylcholines / Q000737:chemistry; D012542:Scattering, Radiation; D013499:Surface Properties
chemical_list: D008051:Lipid Bilayers; D008055:Lipids; D010713:Phosphatidylcholines; C017251:1,2-oleoylphosphatidylcholine