Magnetic Tweezers for Single-Molecule Experiments

  • I. D. Vilfan
  • J. Lipfert
  • D. A. Koster
  • S. G. Lemay
  • N. H. Dekker


Over the last decade, single-molecule techniques have proven their wide applicability in the study of processive motor proteins and other enzymes, yielding insight into their kinetics and mechanochemistry. In the context of force spectroscopy of protein–nucleic acid interactions, optical tweezers, magnetic tweezers, and atomic force microscopy have made important contributions. Advantages of magnetic tweezers include particularly straightforward control of the supercoiled state of DNA, facile extension to parallel measurement of multiple molecules and to integration with fluorescence measurements, and the simplicity and robustness of the experimental configuration. This chapter reviews the principles behind magnetic tweezers and their experimental implementation and points out recent improvements. It also describes several types of experiments that can be performed using magnetic tweezers.


Applied Force Flow Cell Nucleic Acid Molecule Magnetic Tweezer Magnet Geometry 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We thank the many members of our laboratory who have contributed to the research effort using MTs over the last few years. We are particularly grateful to Jeroen Abels for a number of illustrations, to Xiaomin Hao for her help on magnet modeling, to Sven Klijnhout for carrying out the experiments necessary to test the elastic response of twisted DNA, to Zhuangxiong Huang and Gary M. Skinner for help with flow cell coating, and to Serge Lemay for pointing out the alternative derivation of the spring constant of the MT. We also thank Richard H. Ebright and Timothee Lionnet for providing the figures on RNA polymerase scrunching and DNA helicase unwinding, respectively. Funding is acknowledged from the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO) via its Vidi program (IDV and JL), from the Human Frontiers Science Program (DAK), and from the European Science Foundation via a EURYI grant (NHD).


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • I. D. Vilfan
    • 1
  • J. Lipfert
    • 1
  • D. A. Koster
    • 1
  • S. G. Lemay
    • 1
  • N. H. Dekker
    • 1
  1. 1.Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 12628 CJ DelftThe Netherlands

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