Purification of thymine glycol DNA and nucleosides by use of boronate chromatography

Boronate columns can be used to purify DNAs containing cis-thymine glycol residues and can also be used to purify cis-thymine glycol nucleosides. The boronate group can form a reversible complex with the cis-diol of the thymine glycol but not with the urea residue which is formed by alkaline hydrolysis of the thymine glycol. This method is rapid and appears applicable to a range of nucleic acids. In addition to the purifications of DNAs and nucleosides demonstrated here boronate chromatography may be applicable to assaying the extent and sites of oxidative damage to DNAs.