Determination of urinary 8-hydroxy-2'-deoxyguanosine by a combination of on-line molecularly imprinted monolithic solid phase microextraction with high performance liquid chromatography-ultraviolet detection.

8-Hydroxy-2'-deoxyguanosine (8-OHdG) is a sensitive biomarker for DNA oxidative damage. However, its determination in human urine is confounded by trace level and complex matrix. In this study, a new configuration of on-line solid phase microextraction coupled to high performance liquid chromatography-ultraviolet detection was established with molecularly imprinted monolithic column as extraction sorbent. The tailor made monolith exhibited high extraction efficiency with the enrichment factor 101.84 for 8-OHdG owing to its special porous structure and inherent selectivity. Under optimal condition, appreciable sensitivity had been achieved for this incorporation with limit of detection 2.04 nmol/L (S/N = 3) and limit of quantification 7.12 nmol/L (S/N = 10), respectively. Precise determination with wide range linearity (0.007-5.00 μmol/L) afforded a practical alternative in urinary 8-OHdG analysis and 107 different subjects had been successfully analyzed. This newly developed method embodied useful prospect for the investigation of DNA oxidative damage with less expense, convenient maintenance and ease of operation.