title: How to determine local stretching and tension in a flow-stretched DNA molecule.
abstract: We determine the nonuniform stretching of and tension in a mega base pairs-long fragment of deoxyribonucleic acid (DNA) that is flow stretched in a nanofluidic chip. We use no markers, do not know the contour length of the DNA, and do not have the full DNA molecule inside our field of view. Instead, we analyze the transverse thermal motion of the DNA. Tension at the center of the DNA adds up to 16 pN, giving almost fully stretched DNA. This method was devised for optical mapping of DNA, specifically, DNA denaturation patterns. It may be useful also for other studies, e.g., DNA-protein interactions, specifically, their tension dependence. Generally, wherever long strands of DNA-e.g., native DNA extracted from human cells or bacteria-must be stretched with ease for inspection, this method applies.
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345B, DK-2800 Kongens Lyngby, Denmark.
authors.forename: Jonas N
authors.initials: JN
authors.lastname: Pedersen
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345B, DK-2800 Kongens Lyngby, Denmark.
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Marie
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345B, DK-2800 Kongens Lyngby, Denmark.
authors.forename: Anders
authors.initials: A
authors.lastname: Kristensen
authors.affiliation: Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345B, DK-2800 Kongens Lyngby, Denmark.
authors.forename: Henrik
authors.initials: H
authors.lastname: Flyvbjerg
mesh_terms: D020029:Base Pairing; D001696:Biomechanical Phenomena; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D008422:Materials Testing; D055595:Mechanical Phenomena; D008958:Models, Molecular; D009010:Monte Carlo Method; D036103:Nanotechnology; D013696:Temperature
chemical_list: D004247:DNA