title: A liquid chromatography-mass spectrometry method for nicotine and cotinine; utility in screening tobacco exposure in patients taking amiodarone.
abstract: A liquid chromatographic mass spectrometric (LC-MS) assay for the quantification of nicotine and cotinine in human specimens was developed. Human serum and urine (100 μL) were subjected to liquid-liquid extraction. For glucuronidated cotinine, serum was alkalinized and hydrolyzed before extraction. The dried samples were reconstituted and run using gradient flow reverse-phase liquid chromatography with MS detection. The ions utilized for quantification of nicotine, cotinine and milrinone (internal standard) were 162.8, 176.9 and 211.9 m/z, respectively. The mean recoveries were over 80% for cotinine and nicotine with excellent linearity between nominal concentrations and peak area ratios, over a wide concentration range. The percentage coefficient of variation and mean error of the inter- and intra-day validations were <15% for nicotine and cotinine. Analysis of serum from cardiac patients receiving amiodarone suggested that a number of patients were either active smokers or exposed to second-hand smoke. Significant concentrations of nicotine and cotinine were measured in the urine of a known smoking volunteer. The method was highly specific, sensitive and applicable as a tool in detecting and monitoring the passive exposure to tobacco smoke using small specimen volumes (0.1 mL).
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Canada.
authors.forename: Raniah Q
authors.initials: RQ
authors.lastname: Gabr
authors.forename: Marwa E
authors.initials: ME
authors.lastname: Elsherbiny
authors.forename: Vishwa
authors.initials: V
authors.lastname: Somayaji
authors.forename: P Timothy
authors.initials: PT
authors.lastname: Pollak
authors.forename: Dion R
authors.initials: DR
authors.lastname: Brocks
mesh_terms: D000638:Amiodarone / Q000008:administration & dosage*; D002318:Cardiovascular Diseases / Q000097:blood / Q000188:drug therapy / Q000652:urine; D056148:Chromatography, Reverse-Phase / Q000379:methods*; D003367:Cotinine / Q000031:analogs & derivatives / Q000032:analysis* / Q000097:blood / Q000737:chemistry / Q000652:urine; D006801:Humans; D059625:Liquid-Liquid Extraction; D013058:Mass Spectrometry / Q000379:methods*; D020105:Milrinone / Q000032:analysis; D009538:Nicotine / Q000032:analysis* / Q000097:blood / Q000737:chemistry / Q000652:urine; D015203:Reproducibility of Results; D014028:Tobacco Smoke Pollution / Q000032:analysis*
chemical_list: D014028:Tobacco Smoke Pollution; C075991:cotinine N-glucuronide; D009538:Nicotine; D020105:Milrinone; D003367:Cotinine; D000638:Amiodarone