Measurement of oxidized and methylated DNA bases by HPLC with electrochemical detection.

Oxidative DNA damage is thought to be an important contributor to cancer development and to be affected by dietary constituents, so its accurate measurement is important. DNA methylation is recognized as an important mechanism affecting gene expression. In the present paper we describe an HPLC-with-electrochemical-detection procedure that allows rapid and sensitive measurement of four oxidized (2,6-diamino-4-hydroxy-5-formamidopyrimidine, 5-hydroxyuracil, 8-hydroxyguanine, 8-hydroxyadenine) and three methylated (7-methylguanine, 1-methylguanine, O6-methylguanine) bases in acid hydrolysates of DNA. Guanine was also detected, but was clearly separated from the other bases.