Fast Quantification of Salivary 8-Hydroxy-2'-deoxyguanosine as DNA Damage Biomarker Using CE with Electrochemical Detection

The aim of this study was to investigate the correlation between levels of a marker of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OHdG), in human saliva and urine, and to explore its potential application in fast diagnosis of many diseases (especially cancer) associated with oxidative damage. A simple and time-efficient method, based on capillary electrophoresis with electrochemical detection, was developed for the determination of salivary and urinary 8-OHdG. Under the optimum conditions, 8-OHdG and its coexisting analytes could be well separated within 16 min at a voltage of 14 kV in 60 mmol L-1 borax running buffer (pH 8.2). A good linear relationship was established between peak current and concentration of analytes over three orders of magnitude with detection limits (S/N = 3) ranging from 0.41 x 10(-7) to 2.50 x 10(-7) mol L-1 for all analytes.