Spin trapping

An EPR spectrometer used for spin-trapping technique.

Spin trapping is an analytical technique employed in chemistry[1] and biology[2] for the detection and identification of short-lived free radicals through the use of electron paramagnetic resonance (EPR) spectroscopy. EPR spectroscopy detects paramagnetic species such as the unpaired electrons of free radicals. However, when the half-life of radicals is too short to detect with EPR, compounds known as spin traps are used to react covalently with the radical products and form more stable adduct that will also have paramagnetic resonance spectra detectable by EPR spectroscopy.[3] The use of radical-addition reactions to detect short-lived radicals was developed by several independent groups by 1968.[4]

  1. ^ Spin Trapping Concept
  2. ^ Application of Spin Trapping in Biology
  3. ^ Spin Trapping Reagents
  4. ^ A chemical and kinetic evaluation of spin trapping by 5,5-dimethyl-1-pyrroline-N-oxide in the reaction of |FeIIIEDTA|−1 with peroxide, Author: Saunders, Frances Y. 1960- Published: 1990. The paper could be downloaded from archive.org, covering the introduction of Spin Trapping in Page 10:
    In 1968 a special technique called spin-trapping was developed by several independent groups12,16 for the detection and identification of short-lived radicals ... involves the capture of short-lived radicals by a diamagnetic molecule to form a long-lived radical species... and can be easily observed by EPR. ... is a convenient, readily applicable technique which is used extensively ... study of biochemical radical processes.
    The superscript indices 12 and 16 above refer respectively to "Janzen, E. G. In Free Radicals in Biology, Vol. IV; Pryor, W. A., Ed.; New York: Academic Press, 1980; p115", and "Janzen, E. G., Accounts of Chemical Research, 1971, 4.,31."