Finding DNA repair factors: A comparative study with DNAprobes containing 8‐oxodG and bearing different photo‐crosslinking moieties found that a triethyleneglycol‐trifluoromethyl‐phenyldiazirine system was excellent for the labeling of DNA repair factors. This probe was used for the activity‐based and selective labeling of different DNA repair factors in a human HCT‐116 nuclear proteome.