Spin trap is an analytical method used to detect and identify short-lived free radicals and the compounds used for this method. The method of spin traps is to add free radicals formed during any reaction to special acceptors (“spin traps”). It is based on the properties of these compounds to bind free radicals to form more stable radicals, which can be determined from the electron paramagnetic resonance (EPR) spectra.
Content
- 1 History
- 2 Types of spin traps
- 3 See also
- 4 References
History
The use of spin traps for the determination of free radicals was first proposed in 1965 by EG Janzen.
Types of spin traps
Spin traps can be tertiary and aromatic nitroso compounds and nitrons (not to be confused with a polymer fiber nitron ). When they react with free radicals R • nitroxyl radicals or amine radicals are formed. Currently, the most common spin traps are nitrons, in particular N-tert-butyl nitron ( PBN ) and 5.5-dimethylpyrrolin-N-oxide ( DMPO ). Another nitron, 5-diisopropoxyphosphoryl-5-methyl-1-pyrroline-N-oxide ( DIPPMPO ), is used to measure the formation of superoxide in mitochondria .
The reaction product of the 5,5-dimethylpyrrolin-N-oxide with a free radical is so stable that it can be detected not only by EPR, but also by NMR and with the help of specific antibodies to DMPO . The latter method of determining free radicals using anti- DMPO antibodies has found wide application, since it does not require such sophisticated equipment as an EPR spectrometer and allows isolation of reaction products by immunochemical methods.
See also
- Sodium diethyldithiocarbamate
- 2-methyl-2-nitrosopropane