title: Ultrasensitive method for the determination of 4-hydroxy-1-(3-pyridyl)-1-butanone-releasing DNA adducts by gas chromatography-high resolution mass spectrometry in mucosal biopsies of the lower esophagus.
abstract: 4-Hydroxy-1-(3-pyridyl)-1-butanone (HPB)-releasing DNA adducts are formed by metabolic activation of the tobacco-specific nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine (NNN). NNK and NNN are considered carcinogenic to humans by the International Agency for Research on Cancer. Existing analytical methods for determination of HPB-releasing DNA adducts require 0.3-2.0 g of human target tissues such as lung and esophagus. For adduct determination in milligram amounts of biopsy samples, an ultrasensitive and specific method is presented using capillary gas chromatography coupled to a high-resolution mass spectrometer operated in the negative chemical ionization mode (GC-NCI-HRMS). The method has a limit of detection of 4.6 fmol HPB, a limit of quantification of 14.9 fmol HBP and a recovery of 45 +/- 15%. Intra- and inter-day imprecision for N = 6 samples were calculated with coefficients of variation of <3.1%. Method applicability was evaluated with biopsies of esophageal mucosa (N = 14) yielding 5.6 +/- 1.9 mg tissue and a mean adduct level of 6.13 +/- 9.35 pmol HPB/mg DNA.
authors.affiliation: Walther Straub Institute, Department of Toxicology, Ludwig-Maximilians University, Nussbaumstrasse 26, 80336, Munich, Germany.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Heppel
authors.forename: Anne-Kathrin
authors.initials: AK
authors.lastname: Heling
authors.forename: Elmar
authors.initials: E
authors.lastname: Richter
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D002074:Butanones / Q000032:analysis* / Q000378:metabolism; D018736:DNA Adducts / Q000032:analysis* / Q000378:metabolism; D004947:Esophagus / Q000378:metabolism*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000378:metabolism*; D011725:Pyridines / Q000032:analysis* / Q000378:metabolism
chemical_list: D002074:Butanones; D018736:DNA Adducts; D011725:Pyridines; C482281:4-hydroxy-1-(3-pyridyl)-1-butanone