• Editors' Suggestion

Thermophoretic Forces on DNA Measured with a Single-Molecule Spring Balance

Jonas N. Pedersen, Christopher J. Lüscher, Rodolphe Marie, Lasse H. Thamdrup, Anders Kristensen, and Henrik Flyvbjerg
Phys. Rev. Lett. 113, 268301 – Published 30 December 2014
PDFHTMLExport Citation

Abstract

We stretch a single DNA molecule with thermophoretic forces and measure these forces with a spring balance: the DNA molecule itself. It is an entropic spring which we calibrate, using as a benchmark its Brownian motion in the nanochannel that contains and prestretches it. This direct measurement of the thermophoretic force in a static configuration finds forces up to 130 fN. This is eleven times stronger than the force experienced by the same molecule in the same thermal gradient in bulk, where the molecule shields itself. Our stronger forces stretch the middle of the molecule up to 80% of its contour length. We find the Soret coefficient per unit length of DNA at various ionic strengths. It agrees, with novel precision, with results obtained in bulk for DNA too short to shield itself and with the thermodynamic model of thermophoresis.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 7 July 2014

DOI:https://doi.org/10.1103/PhysRevLett.113.268301

© 2014 American Physical Society

Authors & Affiliations

Jonas N. Pedersen, Christopher J. Lüscher, Rodolphe Marie, Lasse H. Thamdrup*, Anders Kristensen, and Henrik Flyvbjerg

  • Department of Micro- and Nanotechnology, Technical University of Denmark, DK-2800 Lyngby, Denmark

  • *Present address: NIL Technology ApS, Diplomvej 381, DK-2800 Kongens Lyngby, Denmark.
  • henrik.flyvbjerg@nanotech.dtu.dk.

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 113, Iss. 26 — 31 December 2014

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review Letters

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×