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Electron Paramagnetic Resonance (EPR) and Spin-labelling

  1. Peter G Fajer

Published Online: 19 FEB 2002

DOI: 10.1038/npg.els.0002985



How to Cite

Fajer, P. G. 2002. Electron Paramagnetic Resonance (EPR) and Spin-labelling. eLS. .

Author Information

  1. Florida State University, Tallahassee, Florida, USA

Publication History

  1. Published Online: 19 FEB 2002


In EPR the magnetic dipole of an electron interacts with an external magnetic field and can be excited by an oscillating magnetic field. Spin labelling involves use of extrinsic probes, nitroxides, attached to the molecule under study. The spectra of nitroxide probes are used to infer orientation, dynamics and distances between labelled sites.


  • magnetic resonance;
  • protein structure;
  • protein dynamics