Stable isotope dilution quantification of mutagens in cooked foods by combined liquid chromatography-thermospray mass spectrometry.
A method of general applicability for the detection and quantification of mutagens in cooked foods at the ppb level is presented. A minimal sample prefractionation is employed and [Me-2H3]-labeled analogs of the compounds of interest are added for identification and quantification of mutagens by accurate measurement of chromatographic retention (K') in reverse-phase high-performance liquid chromatography (HPLC), and by measurement of the ratio of response of the protonated molecular ions of analyte and internal standard by directly coupled liquid chromatography-mass spectrometry (LC/MS). Initial application is demonstrated in the analysis of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) in broiled salmon. Measured levels of IQ and MeIQ in broiled salmon flesh were 0.3-1.8 ppb and 0.6-2.8 ppb, respectively, and for the skin of broiled salmon 1.1-1.7 ppb and 1.5-3.1 ppb, respectively. Results on cooked beef and sardine are also reported.
D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003296:Cooking; D005399:Fishes; D005504:Food Analysis; D006358:Hot Temperature; D013058:Mass Spectrometry / Q000379:methods; D008460:Meat / Q000032:analysis*; D009153:Mutagens / Q000032:analysis*; D011804:Quinolines / Q000032:analysis*; D012474:Salmon
D009153:Mutagens; D011804:Quinolines; C029216:2-amino-3-methylimidazo(4,5-f)quinoline; C036989:2-amino-3,4-dimethylimidazo(4,5-f)quinoline