“…Berliner et al reported the first EPR imaging of a biologically relevant sample as a one-dimensional (1-D) image of a celery stem soaked in a solution of a stable nitroxide radical, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-yloxyl (TEMPOL) . Since then, many in vivo EPR imaging experiments have been successfully carried out in various localized regions of small animals and have shed light on the spatial distribution and pharmacokinetics of exogenously supplied stable radicals such as TEMPOL, 3-carbamoyl-2,2,5,5-tetramethylpyrrolidine-1-yloxyl (carbamoyl-PROXYL), and their analogues. − Furthermore, the oxygen induces the broadening of EPR signals of stable nitroxides and the other paramagnetic agents. Therefore, the application of in vivo EPR spectroscopy to the measurement of concentration or partial pressure of oxygen in tissues has been extensively developed as a promising approach to oxymetry. − This technique has a potential for noninvasive measurement of tissue oxygen status.…”