Improved method for EPR detection of DEPMPO-superoxide radicals by liquid nitrogen freezing

Biochem Biophys Res Commun. 2000 Sep 7;275(3):895-8. doi: 10.1006/bbrc.2000.3387.

Abstract

5-diethoxyphosphoryl-5-methyl-1-pyrroline N-oxide (DEPMPO) is frequently used as a spin trap for the measurement of superoxide by EPR spectrometry. However, its half life is fairly short in room temperature. We here show that superoxide radicals trapped by DEPMPO can be successfully recorded at -196 degrees C. Moreover, we show that the signal intensity remains unaltered for up to 7 days, when the samples are stored in liquid nitrogen. Our new approach for measurement of superoxide should greatly simplify the studies of this important radical in biological systems.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Cyclic N-Oxides / analysis*
  • Electron Spin Resonance Spectroscopy / methods*
  • Freezing
  • Half-Life
  • Kinetics
  • Nitrogen / metabolism*
  • Solutions
  • Spin Labels
  • Superoxide Dismutase / metabolism
  • Superoxides / analysis*
  • Xanthine / metabolism
  • Xanthine Oxidase / metabolism

Substances

  • Cyclic N-Oxides
  • Solutions
  • Spin Labels
  • Superoxides
  • 5-diethoxyphosphoryl-5-methyl-1-pyrroline N-oxide
  • Xanthine
  • Superoxide Dismutase
  • Xanthine Oxidase
  • Nitrogen