title: Fractional polymerization of a suspended planar bilayer creates a fluid, highly stable membrane for ion channel recordings.
abstract: Suspended planar lipid membranes (or black lipid membranes (BLMs)) are widely used for studying reconstituted ion channels, although they lack the chemical and mechanical stability needed for incorporation into high-throughput biosensors and biochips. Lipid polymerization enhances BLM stability but is incompatible with ion channel function when membrane fluidity is required. Here, we demonstrate the preparation of a highly stable BLM that retains significant fluidity by using a mixture of polymerizable and nonpolymerizable phospholipids. Alamethicin, a voltage-gated peptide channel for which membrane fluidity is required for activity, was reconstituted into mixed BLMs prepared using bis-dienoyl phosphatidylcholine (bis-DenPC) and diphytanoyl phosphatidylcholine (DPhPC). Polymerization yielded BLMs that retain the fluidity required for alamethicin activity yet are stable for several days as compared to a few hours prior to polymerization. Thus, these polymerized, binary composition BLMs feature both fluidity and long-term stability.
authors.affiliation: Department of Chemistry and Biochemistry and BIO5 Institute, University of Arizona, Tucson, Arizona 85721, USA.
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Heitz
authors.forename: Ian W
authors.initials: IW
authors.lastname: Jones
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: D000408:Alamethicin / Q000378:metabolism; D007473:Ion Channels / Q000378:metabolism*; D008051:Lipid Bilayers / Q000737:chemistry* / Q000378:metabolism*; D008560:Membrane Fluidity; D008567:Membranes, Artificial; D010713:Phosphatidylcholines / Q000737:chemistry / Q000378:metabolism; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism*; D013535:Suspensions; D013997:Time Factors
chemical_list: D007473:Ion Channels; D008051:Lipid Bilayers; D008567:Membranes, Artificial; D010713:Phosphatidylcholines; D011108:Polymers; D013535:Suspensions; D000408:Alamethicin