3-Carboxy-proxyl
Free radical has been used for calibration of EPR signals for evaluation of amount
of oxidized spin probes like CPH, CMH, PPH and other cyclic hydroxylamine's.
Has been used as s pin-label study molecular migration and long-term stability of
seeds and pollen. The acetoxymethyl ester is an esterase-sensitive probe that crosses
the blood-brain barrier for electron spin resonance-computed tomographic imaging..

Rerferences

1. Fink B, Dikalov S et al. A new approach for extracellular spin trapping of nitroglycerin-induced formation of superoxide radicals both in vitro and in vivo. Free Radical Biology & Medicine 2000; 28(1):121-128. (PDF)
2. Sano, H., A new nitroxyl-probe with high retention in the brain and its application for brain imaging. Free Radic. Biol. Med. 28 , 959, (2000)