title: Single-file electrophoretic transport and counting of individual DNA molecules in surfactant nanotubes.
abstract: We demonstrate a complete nanotube electrophoresis system (nanotube radii in the range of 50 to 150 nm) based on lipid membranes, comprising DNA injection, single-molecule transport, and single-molecule detection. Using gel-capped electrodes, electrophoretic single-file transport of fluorescently labeled dsDNA molecules is observed inside nanotubes. The strong confinement to a channel of molecular dimensions ensures a detection efficiency close to unity and identification of DNA size from its linear relation to the integrated peak intensity. In addition to constituting a nanotechnological device for identification and quantification of single macromolecules or biopolymers, this system provides a method to study their conformational dynamics, reaction kinetics, and transport in cell-like environments.
authors.affiliation: Department of Chemistry and Bioscience, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
authors.forename: Michal
authors.initials: M
authors.lastname: Tokarz
authors.forename: Björn
authors.initials: B
authors.lastname: Akerman
authors.forename: Jessica
authors.initials: J
authors.lastname: Olofsson
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Joanny
authors.forename: Paul
authors.initials: P
authors.lastname: Dommersnes
authors.forename: Owe
authors.initials: O
authors.lastname: Orwar
mesh_terms: D010584:Bacteriophage phi X 174 / Q000378:metabolism; D001692:Biological Transport; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D004566:Electrodes; D004586:Electrophoresis / Q000379:methods*; D005456:Fluorescent Dyes / Q000494:pharmacology; D007700:Kinetics; D008055:Lipids / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry; D018613:Microscopy, Confocal; D043942:Nanotubes / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D009995:Osmosis; D011487:Protein Conformation; D018030:Silver Compounds / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013025:Glycine max / Q000378:metabolism; D013501:Surface-Active Agents / Q000737:chemistry* / Q000378:metabolism; D013696:Temperature
chemical_list: D005456:Fluorescent Dyes; D008055:Lipids; D008081:Liposomes; D018030:Silver Compounds; D012997:Solvents; D013501:Surface-Active Agents; D004247:DNA; C037548:silver chloride