Measurements of pO2 in Vivo, Including Human Subjects, by Electron Paramagnetic Resonance
The purpose of this paper is to provide an illustrative description of the current state of development of the use of electron paramagnetic resonance (EPR, or completely equivalently, electron spin resonance or ESR) to measure the partial pressure of oxygen (pO2) in tissues in vivo under physiological conditions. This summary is based on published and unpublished results from our laboratory (1–7) and does not attempt to describe the results of other laboratories which also are working along related lines (8–10). The pertinent features of our technique are illustrated. We also consider the current limitations of the technique and likely developments in the near future. Our evaluation is that: this technique now is suitable for immediate use in small animals; within a short period of time instruments will be available facilitating its use in larger animals; and preliminary studies are imminent in human subjects (7).
KeywordsElectron Paramagnetic Resonance Paramagnetic Species Paramagnetic Material Nitroxide Spin Label Paramagnetic Agent
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