Biomarker analysis of hemoglobin adducts of acrylamide and glycidamide enantiomers for mid-term internal exposure assessment by isotope dilution ultra-high performance liquid chromatography tandem mass spectrometry

Abstract Hemoglobin (Hb) adducts of acrylamide (AA) and its oxidative metabolite glycidamide (GA) are important biomarkers for evaluating the mid-term exposure of acrylamide toxicity in vivo. Taking pentafluoro-2-methylphenyl isothiocyanates of N-(2-carbamoylethyl)valine (AAVal-PFPTH) and N-(2-carbamoyl-2-hydroxyethy)valine (GAVal-PFPTH) as target analytes, we developed an isotope dilution ultra-high performance liquid chromatograph tandem mass spectrometry (UHPLC-MS/MS) method for the simultaneous determination of AA and GA hemoglobin (Hb) adducts under the electroscopy ionization negative (ESI‾) mode in the present work. Among them, the enantiomer pair of GA-Hb adducts was firstly identified and successfully separated at baseline level. The method achieved high sensitivity with the LOD and LOQ ranging 1.43–5.05 pmol/g Hb and 4.78–16.82 pmol/g Hb, respectively. The recovery rates with low, intermediate and high spiking levels were calculated as 97.0–105.2%, 97.4–106.4% and 100.3–111.2%, respectively. Acceptable within-laboratory reproducibility (RSD