Quantitative Analysis of DNA Adducts

The analyses were performed using a Waters Xevo G2-XS quadrupole-time
of flight mass spectrometer for compound characterization in HR (Supporting
Information, section “Supplementary Results,” MS And MS/MS Characterization) and a Waters Xevo TQ-XS
(triple quadrupole) mass spectrometer both equipped with Z-spray (electrospray)
ionization and step-wave source optimization, and controlled under
MassLynx v4.2 (Waters) as fully described previously.^{13 (link)} The Waters Xevo G2-XS was used for the compounds characterization
in HR, in full-scan, and in quadrupole selection mode without or with
increasing collision energy up to 35 V for fragment generation. The
Waters Xevo TQ-XS was used for the implementation of the MRM method
as detailed in Supporting Information, section “Supplementary Results” and Table S1. The final
MRM transitions for O6-m2dGO and 2dGO analyses are given in Table 2 with expected LC
retention times of each compound and selected MRM transitions for
LC method optimization.
MassLynx and TargetLynx v.4.2 (Waters) were used for
rapid chromatogram
and spectra evaluation and for the construction of calibration curves
and the computing of quantification data, respectively. As only 60
μL out of 65 μL was taken from each sample for analysis
and CALs were prepared as 60 μL-samples, calculated concentrations
were corrected by a factor 1.083 to retrieve real concentrations in
the samples.