Sensitive and rapid method for the determination of urinary cotinine in non-smokers: an application for studies assessing exposures to second hand smoke (SHS)

• Published in: Analytica chimica acta Vol. 545; no. 2; pp. 200 - 208
• Main Authors: Song, Liguo, Davis, Warren, Abrams, Sara M., Hemiup, Jeremy, Latif Kazim, A., Michael Cummings, K., Mahoney, Martin C.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 27.07.2005; Elsevier
• Subjects: Analytical chemistry; Chemistry; Chromatographic methods and physical methods associated with chromatography; Cotinine; Electrospray ionization; Exact sciences and technology; Liquid chromatography; Other chromatographic methods; Second hand smoke; Spectrometric and optical methods; Tandem mass spectrometry; Tandem mass spectrometry; Second hand smoke; Liquid chromatography; Cotinine; Electrospray ionization; Urine; Ammonium; Elution; Chemical analysis; Liquid liquid extraction; Cotinine: Liquid chromatography; Acetate; Electrospray; Chemical ionization; Quadrupole spectrometer; Chemical enrichment; Sample preparation; Chlorides; Detection limit; Mass spectrometry MS/MS; Acetonitrile; Mass spectrometry; Monitoring; Nicotine
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2005.04.051

We describe a sensitive and rapid method to assay urinary cotinine levels among non-smokers using liquid chromatography-electrospray ionization tandem mass spectrometry (LC–ESI/MS/MS) and its application in studies assessing exposures to second hand smoke (SHS). Cotinine was initially extracted from 1 ml of urine with methylene chloride by using a liquid–liquid extraction Chem Elut™ column. The extracted sample was further separated by using a BetaBasic C18 column (1 mm × 150 mm, 3 μm) with isocratic elution (60:40 acetonitrile and 5 mM ammonium acetate at pH 5), and then examined using a triple quadrupole mass spectrometer with an electrospray ionization (ESI) source in multiple-reaction-monitoring (MRM) mode. The elution of cotinine from the LC column took approximately 2.3 min and the detection of cotinine by ESI/MS/MS provided a limit of detection (LOD) of 0.3 ng/ml. The ESI/MS/MS detection was able to easily distinguish between cotinine and nicotine. This method, validated using a cotinine concentration range from 0.8 to 102.4 ng/ml, was successfully applied in a cross-sectional study examining differences in levels and sources of second hand smoke (SHS) exposure among non-smokers. Self-reported measures of SHS exposure were significantly associated with urinary cotinine levels. This urinary cotinine assay using LC–ESI/MS/MS provides a robust, high throughput and very sensitive method for the evaluation of SHS exposure for use in epidemiologic and clinical research studies.