Use of continine immunoassay test strips for preclassifying urine samples from smokers and nonsmokers prior to analysis by LC-MS-MS.
Cotinine biomarker measurements involving both smokers and nonsmokers must accommodate a broad range of concentrations. Thus, we have routinely preclassified unknown samples as being either "high" or "low" by using an enzyme-linked immunoassay for cotinine prior to analysis by tandem mass spectrometry (MS). Although this method is effective, it is also time-consuming and complex; a simpler and faster approach would be useful. Consequently, a screening assay for urine cotinine using an immunochromatographic test strip (NicAlert) followed by a computerized analysis of the data was examined as a possible alternative. The results indicate that this approach can provide useful classification efficiency when using our target cutoff value of approximately 20 ng/mL. In the analysis of 50 urine samples from nonsmokers with varying degrees of exposure to environmental tobacco smoke, the classification sensitivity and specificity were 88% and 92%, respectively, for cotinine measured by the test strips relative to total cotinine concentrations measured by atmospheric-pressure ionization tandem MS. However, the relatively high cost of the strips may be a limiting factor.
Bernert
John T
JT
Tobacco Exposure Biomarkers Laboratory, Division of Laboratory Science, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Highway, NE, Atlanta, GA 30341, USA. jtb2@cdc.gov
Harmon
Tia L
TL
Sosnoff
Connie S
CS
McGuffey
James E
JE
D002138:Calibration; D002853:Chromatography, Liquid; D003367:Cotinine / Q000652:urine*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007118:Immunoassay; D011934:Reagent Strips; D012907:Smoking / Q000652:urine*; D021241:Spectrometry, Mass, Electrospray Ionization; D014028:Tobacco Smoke Pollution
D011934:Reagent Strips; D014028:Tobacco Smoke Pollution; D003367:Cotinine