title: Polymerized planar suspended lipid bilayers for single ion channel recordings: comparison of several dienoyl lipids.
abstract: The stabilization of suspended planar lipid membranes, or black lipid membranes (BLMs), through polymerization of mono- and bis-functionalized dienoyl lipids was investigated. Electrical properties, including capacitance, conductance, and dielectric breakdown voltage, were determined for BLMs composed of mono-DenPC, bis-DenPC, mono-SorbPC, and bis-SorbPC both prior to and following photopolymerization, with diphytanoyl phosphocholine (DPhPC) serving as a control. Poly(lipid) BLMs exhibited significantly longer lifetimes and increased the stability of air-water transfers. BLM stability followed the order bis-DenPC > mono-DenPC ≈ mono-SorbPC > bis-SorbPC. The conductance of bis-SorbPC BLMs was significantly higher than that of the other lipids, which is attributed to a high density of hydrophilic pores, resulting in relatively unstable membranes. The use of poly(lipid) BLMs as matrices for supporting the activity of an ion channel protein (IC) was explored using α-hemolysin (α-HL), a model IC. Characteristic i-V plots of α-HL were maintained following photopolymerization of bis-DenPC, mono-DenPC, and mono-SorbPC, demonstrating the utility of these materials for preparing more durable BLMs for single-channel recordings of reconstituted ICs.
authors.affiliation: Department of Chemistry and Biochemistry and BIO5 Institute, University of Arizona, 1306 East University Boulevard, Tucson, Arizona 85721, United States.
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Heitz
authors.forename: Juhua
authors.initials: J
authors.lastname: Xu
authors.forename: Ian W
authors.initials: IW
authors.lastname: Jones
authors.forename: John P
authors.initials: JP
authors.lastname: Keogh
authors.forename: Troy J
authors.initials: TJ
authors.lastname: Comi
authors.forename: Henry K
authors.initials: HK
authors.lastname: Hall
authors.forename: Craig A
authors.initials: CA
authors.lastname: Aspinwall
authors.forename: S Scott
authors.initials: SS
authors.lastname: Saavedra
mesh_terms: D025802:Electric Capacitance; D004553:Electric Conductivity; D006460:Hemolysin Proteins / Q000378:metabolism; D007473:Ion Channels / Q000378:metabolism*; D008051:Lipid Bilayers / Q000737:chemistry* / Q000378:metabolism*; D010767:Phosphorylcholine / Q000737:chemistry / Q000378:metabolism; D058105:Polymerization; D013535:Suspensions
chemical_list: D006460:Hemolysin Proteins; D007473:Ion Channels; D008051:Lipid Bilayers; D013535:Suspensions; D010767:Phosphorylcholine