Spin-trapping detection of precursors of hydroxyl-radical-induced DNA damage: identification of precursor radicals of DNA strand breaks in oligo(dC)10 and oligo(dT)10

Oligonucleotides reveal precursors of strand breaks which are stimulated by the hydroxyl radical, whose occurrence is determined by using a spin-trapping process along with enzymatic digestion and high-performance liquid chromatography. The spin trap 2-methyl-2-nitrosopropane is used to capture the radicals generated as precursors of the strand breaks and the base modifications. Nitroxide segments which are low in molecular weight are formed when snake venom phosphodiesterase digests the oligonucleotides which have spin adducts. High-performance liquid chromatography is used to locate various spin adducts.