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Site-directed Spin Labeling and Pulse Dipolar Electron Paramagnetic Resonance

Nuclear Magnetic Resonance and Electron Spin Resonance Spectroscopy

  1. Johann P. Klare,
  2. Heinz-Jürgen Steinhoff

Published Online: 15 MAY 2010

DOI: 10.1002/9780470027318.a9024

Encyclopedia of Analytical Chemistry

Encyclopedia of Analytical Chemistry

How to Cite

Klare, J. P. and Steinhoff, H.-J. 2010. Site-directed Spin Labeling and Pulse Dipolar Electron Paramagnetic Resonance. Encyclopedia of Analytical Chemistry. .

Author Information

  1. University of Osnabrueck, Physics Department, Osnabrueck, Germany

Publication History

  1. Published Online: 15 MAY 2010


Structural and functional investigations on biomolecules often rely on the availability of topological information, either to allow building structural models or to characterize conformational changes of these molecules or complexes thereof during function. Site-directed spin labeling (SDSL) in combination with EPR spectroscopy became a very powerful tool to obtain intra- and inter-molecular distance constraints, as the accessible distances span the interesting range from 0.5–8 nm, crystallization is not required, and the size of the system under investigation is not limited. Especially the development of pulse dipolar EPR methods, in particular double electron–electron resonance (DEER) spectroscopy with its ability to provide interspin distance distributions in the 2–8 nm range, greatly increased the applicability of electron paramagnetic resonance (EPR) spectroscopy for studies on biological systems. This article is intended to give an introduction into SDSL and dipolar EPR. The first part summarizes the state-of-the-art in SDSL, providing an overview of methodologies currently available or under development. In the second part, the technique of DEER spectroscopy is introduced, covering the basic theoretical background as well as selected practical aspects of data acquisition and analysis. Finally, selected examples for the application of SDSL-DEER from the recent literature are summarized.


  • site-directed spin labeling;
  • SDSL;
  • electron paramagnetic resonance;
  • EPR;
  • pulse EPR;
  • double electron–electron resonance;
  • DEER;
  • pulse double electron resonance;
  • distance determination;
  • spin label;
  • MTSSL;
  • four-pulse DEER