Fast and Simultaneous Determination of Urinary 8-Hydroxy-2′-deoxyguanosine and Ten Monohydroxylated Polycyclic Aromatic Hydrocarbons by Liquid Chromatography/Tandem Mass Spectrometry

8-Hydroxy-2'-deoxyguanosine (8-OHdG), a biomarker of oxidative DNA damage, has been extensively studied to assess human exposure to carcinogenic compounds. Previous studies have associated levels of human urinary hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) with those of 8-OHdG. However, measurements of OH-PAHs and 8-OHdG in urine are often conducted with two different analytical methods, which is both costly and time-consuming. In this study, a novel method is described to quickly and simultaneously quantify ten urinary OH-PAHs and 8-OHdG through high pressure liquid chromatography/tandem mass spectrometry (HPLC/MS/MS). Urine samples undergo solid phase extraction and concentration and then are analyzed by an optimized HPLC/MS/MS method operated in the negative electrospray ionization (ESI) and multiple reaction monitoring (MRM) mode. Deuterated, N-15 and C-13- labeled analogues are used as internal standards. Simultaneous analysis of urinary 8-OHdG and OH-PAHs are completed within 16 min. Calibration curves of all target analytes show favorable linearity within the concentration range of 0.3-10.0 mu g/L for 8-OHdG and 0.05-15 mu g/L for different OH-PAHs. The method detection limits (MDLs) in pooled urine range from 0.023 mu g/L to 0.625 mu g/L. The method shows satisfactory accuracy and precision when we analyzed varied levels spiked in pooled urine. Recoveries for 8 of the 10 OH-PAHs were in the range of 100 +/- 15% with a variation coefficient of less than 20%. Thirty-four real urine samples were analyzed for all target analytes. Except 3-OHF, most compounds could be quantified.