Biological radicals resulted from oxidative stress has been implicated in human diseases, such as cancer and aging. There is, however, a paucity of reliable methods for in vivo or ex vivo detection of either radical formation, the end-products of radical formation or susceptibility for radical formation. The chicken polyclonal anti-DMPO can be used to detect the stable nitrone end-product of protein and DNA radicals in ELISA assays, blot analyses and confocal microscopy. This chicken polyclonal anti-DMPO antiserum will supplement both the mouse monoclonal anti-DMPO and the rabbit polyclonal anti-DMPO. The availability of anti-DMPO from three different sources will greatly expand the ability of researchers to use anti-DMPO in conjunction with other antibodies.