Detection of Free Radicals Generated from the in vitro Metabolism of Carbon Tetrachloride Using Improved ESR Spin Trapping Techniques

The spin trapping chemistry of carbon tetrachloride has been previously investigated in rat liver, both in vitro and in vivo. In addition to the trichloromethyl radical, both a 'carbon-centred' and an 'oxygen-centred' radical have been detected in vitro. These spin adducts have been assigned to 'lipid' and 'lipid oxyl' radicals. However, no specific structural characterization has been provided to date. The spin trapping chemistry of this system was reinvestigated with the use of deuterated α-phenyl N-tert-butyl nitrones to obtain better spectral resolution. Results indicate that the PBN trapped carbon-centred lipid radical is of a primary alkyl type.