Open AccessComparison of SemiQuantitative Cotinine Values Obtained by the DRI Immunoassay and Values Obtained by a Liquid Chromatography–Tandem Mass Spectrometry‐Based Method: The DRI Immunoassay is Suitable for Screening Purposes Only Because Semiquantitative Values May Be Unreliable
Author(s) -
Dixon R. Brent,
Dasgupta Amitava
Publication year - 2016
Publication title -
journal of clinical laboratory analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 50
eISSN - 1098-2825
pISSN - 0887-8013
DOI - 10.1002/jcla.21988
Subject(s) - cotinine , chromatography , immunoassay , urine , chemistry , liquid chromatography–mass spectrometry , mass spectrometry , tandem mass spectrometry , nicotine , medicine , biochemistry , antibody , immunology
Background DRI cotinine assay is suitable only for screening for cotinine in urine specimens. We studied the reliability of DRI cotinine semiquantitative values by comparing them with the cotinine concentration obtained with a liquid chromatography–tandem mass spectrometry ( LC ‐ MS / MS ) method. Methods Semiquantitative cotinine concentrations in 39 urine specimens obtained by the DRI immunoassay were compared with cotinine concentrations obtained by LC ‐ MS / MS . Results The DRI cotinine assay consistently overestimated cotinine values obtained by the LC / MS / MS method ( y = 1.1529 x + 252.24, n = 39, R 2 = 0.8899) indicating that semiquantitative values obtained using the DRI assay may be unreliable. However, no false‐negative results were observed using the DRI assay. Conclusion DRI cotinine assay is suitable only for screening cotinine in urine specimens.