A method of analyzing NMR images obtained using proton-electron double-resonance imaging (PEDRI) to image free-radical distributions is presented. The dependence of image intensity on proton mobility within the sample is demonstrated for samples of the nitroxide free radical TEMPOL in water/glycerol mixtures of different viscosities. From the images obtained at a fixed magnetic field strength of 10 mT, the parameters which are responsible for the image dependence on viscosity are determined. Field-cycling techniques are used to measure this dependence as a function of magnetic field strength with a view to defining a single parameter reflecting changes in proton mobility within a sample of unknown concentration.
ASJC Scopus subject areas