Determination of the food carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in human hair by solid-phase extraction and gas chromatography-mass spectrometry

Department of Chemistry, University of Oslo, Kristiania (historical), Oslo, Norway
Chromatographia (Impact Factor: 1.37). 04/2012; 52(7):499-504. DOI: 10.1007/BF02535726

ABSTRACT A method for the determination of the food mutagen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in human hair has been developed and validated. Hair samples (200 mg) were dissolved in NaOH (1 M) and PhIP
was isolated by successive solid-phase extraction on a polystyrene-divinylbenzene column and on a silica-based mixed-mode
column with C8 and-SO3
− functional groups. Quantification was performed by gas chromatography-electron-impact ionization high-resolution mass spectrometry
in selected-ion-monitoring mode. The method was validated for determination of PhIP in the concentration range 0.5–25 ng g−1 hair with [2H3]PhIP as internal standard. The limit of quantification was 0.26 ng g−1 hair. Within-day and between-day precision were in the ranges 1–27% and 2–15% relative standard deviation, respectively.
The hair sample used for method validation was found to contain 0.26 ng PhIP g−1 hair.

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