title: Simple, Direct Routes to Polymer Brush Traps and Nanostructures for Studies of Diffusional Transport in Supported Lipid Bilayers.
abstract: Patterned poly(oligo ethylene glycol) methyl ether methacrylate (POEGMEMA) brush structures may be formed by using a combination of atom-transfer radical polymerization (ATRP) and UV photopatterning. UV photolysis is used to selectively dechlorinate films of 4-(chloromethyl)phenyltrichlorosilane (CMPTS) adsorbed on silica surfaces, by exposure either through a mask or using a two-beam interferometer. Exposure through a mask yields patterns of carboxylic acid-terminated adsorbates. POEGMEMA may be grown from intact Cl initiators that were masked during exposure. Corrals, traps, and other structures formed in this way enable the patterning of proteins, vesicles, and, following vesicle rupture, supported lipid bilayers (SLBs). Bilayers adsorbed on the carboxylic acid-terminated surfaces formed by C-Cl bond photolysis in CMPTS exhibit high mobility. SLBs do not form on POEGMEMA. Using traps consisting of carboxylic acid-functionalized regions enclosed by POEGMEMA structures, electrophoresis may be observed in lipid bilayers containing a small amount of a fluorescent dye. Segregation of dye at one end of the traps was measured by fluorescence microscopy. The increase in the fluorescence intensity was found to be proportional to the trap length, while the time taken to reach the maximum value was inversely proportional to the trap length, indicating uniform, rapid diffusion in all of the traps. Nanostructured materials were formed using interferometric lithography. Channels were defined by exposure of CMPTS films to maxima in the interferogram, and POEGMEMA walls were formed by ATRP. As for the micrometer-scale patterns, bilayers did not form on the POEGMEMA structures, and high lipid mobilities were measured in the polymer-free regions of the channels.
authors.affiliation: Department of Chemistry, University of Sheffield , Brook Hill, Sheffield S3 7HF, United Kingdom.|Krebs Institute, University of Sheffield , Sheffield S10 2TN, United Kingdom.
authors.forename: Alexander
authors.initials: A
authors.lastname: Johnson
authors.affiliation: Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds , Leeds LS2 9JT, United Kingdom.
authors.forename: Peng
authors.initials: P
authors.lastname: Bao
authors.affiliation: Department of Chemistry, University of Sheffield , Brook Hill, Sheffield S3 7HF, United Kingdom.
authors.forename: Claire R
authors.initials: CR
authors.lastname: Hurley
authors.affiliation: Department of Molecular Biology and Biotechnology, University of Sheffield , Western Bank, Sheffield S10 2TN, United Kingdom.
authors.forename: Michaël
authors.initials: M
authors.lastname: Cartron
authors.affiliation: Molecular and Nanoscale Physics Group, School of Physics and Astronomy, University of Leeds , Leeds LS2 9JT, United Kingdom.
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Evans
authors.affiliation: Department of Molecular Biology and Biotechnology, University of Sheffield , Western Bank, Sheffield S10 2TN, United Kingdom.
authors.forename: C Neil
authors.identifier: 0000-0003-2533-9783
authors.initials: CN
authors.lastname: Hunter
authors.affiliation: Department of Chemistry, University of Sheffield , Brook Hill, Sheffield S3 7HF, United Kingdom.|Krebs Institute, University of Sheffield , Sheffield S10 2TN, United Kingdom.
authors.forename: Graham J
authors.identifier: 0000-0002-4315-9076
authors.initials: GJ
authors.lastname: Leggett
mesh_terms: D008051:Lipid Bilayers; D008689:Methacrylates; D049329:Nanostructures; D058105:Polymerization; D011108:Polymers; D013499:Surface Properties
chemical_list: D008051:Lipid Bilayers; D008689:Methacrylates; D011108:Polymers