Simultaneous HPLC-MS determination of 8-hydroxy-2′-deoxyguanosine, 3-hydroxyphenanthrene and 1-hydroxypyrene after online in-tube solid phase microextraction using a graphene oxide/poly(3,4-ethylenedioxythiophene)/polypyrrole composite

The exploration of monohydroxy polycyclic aromatic hydrocarbons and 8-hydroxy-2′-deoxyguanosine (8-OHdG) produced by oxidative stress and DNA damage is a powerful and non-invasive tool to study the health risk of exposure to polycyclic aromatic hydrocarbons (PAHs). A nanocomposite prepared from graphene oxide, poly(3,4-ethylenedioxythiophene) and polypyrrole was electrodeposited on the internal surface of a stainless-steel tube for online in-tube solid phase microextraction (IT-SPME) of 8-OHdG, 3-hydroxyphenanthrene and 1-hydroxypyrene from urine. The coating possesses excellent chemical and mechanical stability, high extraction efficiency, good resistance to matrix interference, and a long lifespan. An online IT-SPME-high performance liquid chromatography-mass spectrometry method was developed for the determination of these three metabolite biomarkers in human urine. Figures of merit include (a) enrichment factors of 30–48; (b) low limits of detection (4–41 pg·mL −1 at S/ N  = 3); (c) wide linear ranges (0.05–50 ng·mL −1 ); (d) good recoveries from spiked samples (71.6–109.5%); and (e) acceptable repeatability (2.3–14.6%). The method offers the advantages of low cost, simplicity, sensitivity, rapidity and automation. Schematic illustration of online in-tube solid phase microextraction using graphene oxide/poly(3,4-ethylenedioxythiophene)/polypyrrole composites as adsorbent in a stainless-steel (SS) tube for the enrichment and simultaneous determination of 8-hydroxy-2′-deoxyguanosine, 3-hydroxyphenanthrene and 1-hydroxypyrene prior to HPLC-MS analysis.