Capillary electrophoretic determination of DNA damage markers: Content of 8-hydroxy-2′-deoxyguanosine and 8-nitroguanine in urine

A sensitive and low-cost analytical method has been developed to determine 8-hydroxy-2′-deoxyguanosine (8-OHdG) and 8-nitroguanine (8-NO2Gua) based on capillary electrophoresis with amperometric detection (CE–AD) after solid phase extraction (SPE). Under optimized condition, these two markers were well separated from other components coexisting in urine, exhibiting a linear calibration over the concentration range of 0.1–50.0 μg/mL with the detection limits ranging from 0.02 to 0.06 μg/mL. The relative standard deviations (RSDs) were in the range of 0.1–2.1% for peak area, 0.1–1.5% for migration time, respectively. The average recovery and RSD were within the range of 100.0–108.0% and 0.1–1.7%, respectively. It was found that the urinary contents of 8-OHdG and 8-NO2Gua in cancer patients were significantly higher than those in healthy ones.