Detection of Hydroxylated Metabolites of Polycyclic Aromatic Hydrocarbons by Electrospray Ionization Ion Trap Tandem Mass Spectrometry

Hydroxylated metabolites of polycyclic aromatic hydrocarbons (OH-PAHs) are the mostly widely used biomarker of carcinogenic PAHs to assess health risk caused by exposure to PAHs. Among present strategies used for detecting OH-PAHs, electrospray ionization tandem mass spectrometry(ESI-MS2) shows advantages in both high sensitivity and selectivity; however, fragment ions cannot be obtained for some OH-PAHs (e. g. 3-OHBaP, 2-OHFlu). In this work, ESI-MS2 analysis of nine OH-PAHs(2- to 5-rings) was achieved with ion trap MS2(IT-MS2); by optimizing collision-induced dissociation conditions of activation Q(AQ) and normalized collision energy(NCE), 3-OHBaP and 2-OHFlu were effectively fragmented meanwhile fragmentation efficiencies of other seven OH-PAHs were also improved. AQ was proven to be the critical parameter for fragmenting OH-PAHs when IT-MS2 is used.