Detection of DNA base damage by 32P-postlabelling: TLC separation of 5'-deoxynucleoside monophosphates

Traces of damaged bases in DNA can be detected without the use of radioactive chemical agent or radiolabelled DNA substrate by incorporation of radiolabel into DNA after exposure to the chemical. This postlabelling approach to carcinogen adduct analysis is potentially useful for adduct detection in the DNA of humans exposed to carcinogens. We describe here the postlabelling analysis of DNA by chromatography of deoxynucleoside monophosphates. Separation and characterization of modified residues in nucleotide digests of DNA treated in vitro with chloroacetaldehyde is demonstrated.