Subpicogram per milliliter determination of the tobacco-specific carcinogen metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol in human urine using liquid chromatography-tandem mass spectrometry.
Exposure to secondhand tobacco smoke (SHS) has been linked to increased risk for a number of diseases, including lung cancer. The tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is of particular interest due to its potency and its specificity in producing lung tumors in animals. The NNK metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) in urine is frequently used as a biomarker for exposure. Due to its long half-life (40-45 days), NNAL may provide a long-term, time-averaged measure of exposure. We developed a highly sensitive liquid chromatography-tandem mass spectrometry method for determination of NNAL in human urine. The method involves liquid-liquid extraction followed by conversion to the hexanoate ester derivative. This derivative facilitates separation from interfering urinary constituents by extraction and chromatography and enhances detection with electrospray ionization mass spectrometry. The lower limit of quantitation is 0.25 pg/mL for 5-mL urine specimens. Applications to studies of people with a range of different SHS exposure levels is described.
Division of Clinical Pharmacology, University of California, San Francisco, UCSF Box 1220, San Francisco, California 94143-1220, USA. peyton.jacob@ucsf.edu
Peyton
P
Jacob
Christopher
C
Havel
Do-Hoon
DH
Lee
Lisa
L
Yu
Mark D
MD
Eisner
Neal L
NL
Benowitz
D002138:Calibration; D002273:Carcinogens / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D002853:Chromatography, Liquid / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D015394:Molecular Structure; D009602:Nitrosamines / Q000737:chemistry / Q000652:urine*; D011725:Pyridines / Q000737:chemistry / Q000652:urine*; D053719:Tandem Mass Spectrometry / Q000295:instrumentation* / Q000379:methods*
D002273:Carcinogens; D009602:Nitrosamines; D011725:Pyridines; C099565:4-(methylnitrosamino)-1-(3-pyridyl)-1-butan-1-ol