Analysis of nicotine and cotinine in hair by on-line in-tube solid-phase microextraction coupled with liquid chromatography-tandem mass spectrometry as biomarkers of exposure to tobacco smoke.

Smoking not only increases the risk of lung cancer but is strongly related to the onset of cardiovascular disease. Particularly, passive smoking due to sidestream smoke is a critical public health problem. To assess active and passive exposure to tobacco smoke, we developed a simple and sensitive method, consisting of on-line in-tube solid phase microextraction (SPME) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS), to determine nicotine and its metabolite cotinine in hair samples. These compounds were separated within 5 min using a Polar-RP80A column and detected in the positive ion mode by multiple reaction monitoring. The optimum in-tube SPME conditions were 25 draw/eject cycles of 40 μL of sample at a flow rate of 200 μL/min using a Carboxen 1006 capillary column as an extraction device. The extracted compounds in the stationary phase on the inner wall of the capillary could be dissolved easily into the mobile phase and transferred to an LC column. Using the in-tube SPME LC-MS/MS method, the calibration curves were linear in the 5-1000 pg/mL ranges for nicotine and cotinine, and the detection limits (signal to noise ratio of 3) were 0.45 and 0.13 pg/mL, respectively. The intra-day and inter-day precisions were below 3.4% and 6.0% (n = 5), respectively. This method was utilized successfully to analyze pg/mg levels of nicotine and cotinine in 1 mg of hairs without interference peaks, and good recoveries were obtained. The concentration of cotinine in hair was two orders of magnitude lower than that of nicotine, but a good positive correlation was found between the concentrations of these compounds. This method can automate the extraction, concentration and analysis of samples, and is useful for the assessment of long-term exposure to tobacco smoke.

Inukai T ，Kaji S ，Kataoka H 《-》

Determination of nicotine, cotinine, and related alkaloids in human urine and saliva by automated in-tube solid-phase microextraction coupled with liquid chromatography-mass spectrometry.

Kataoka H ，Inoue R ，Yagi K ，Saito K ... -  《JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS》

Risk Assessment of Passive Smoking Based on Analysis of Hair Nicotine and Cotinine as Exposure Biomarkers by In-Tube Solid-Phase Microextraction Coupled On-Line to LC-MS/MS.

Kataoka H ，Kaji S ，Moai M 《MOLECULES》

Analysis of heterocyclic amines in hair by on-line in-tube solid-phase microextraction coupled with liquid chromatography-tandem mass spectrometry.

Mutagenic and carcinogenic heterocyclic amines (HCAs) are formed during heating of various proteinaceous foods, but human exposure to HCAs has not yet been elucidated in detail. To assess long-term exposure to HCAs, we developed a simple and sensitive method for measuring HCAs in hair by automated on-line in-tube solid-phase microextraction (SPME) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Using a Zorbax Eclipse XDB-C8 column, 16 HCAs were analyzed within 15 min. The optimum in-tube SPME conditions were 20 draw/eject cycles of 40 μL sample at a flow rate of 200 μL min(-1) using a Supel-Q PLOT capillary column as an extraction device. The extracted HCAs were easily desorbed from the column by passage of the mobile phase, with no carryover observed. This in-tube SPME LC-MS/MS method showed good linearity for HCAs in the range of 10-2000 pg mL(-1), with correlation coefficients above 0.9989 (n=18), using stable isotope-labeled HCA internal standards. The detection limits (S/N=3) of 14 HCAs except for MeAαC and Glu-P-1 were 0.10-0.79 pg mL(-1). This method was successfully utilized to analyze 14 HCAs in hair samples without any interference peaks, with quantitative limits (S/N=10) of about 0.17-1.32 pg mg(-1) hair. Using this method, we evaluated the exposure to HCAs in cigarette smoke and the suitability of using hair HCAs as exposure biomarkers.

Kataoka H ，Inoue T ，Saito K ，Kato H ，Masuda K ... -  《-》

Simultaneous Determination of Tobacco Smoke Exposure and Stress Biomarkers in Saliva Using In-Tube SPME and LC-MS/MS for the Analysis of the Association between Passive Smoking and Stress.

Kataoka H ，Miyata S ，Ehara K 《MOLECULES》