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The free and bound volatiles of tobaccos were analyzed by capillary GC and GC-MS. Bound volatiles were isolated by dichloromethane extraction followed by stream distillation continuous extraction (SDE) at pH 2.5 acid hydrolysis. The bound aromatic compounds were hydrolyzed by acid at pH 2.5, and the
The mutagenicity of particulate matter concentrated from environmental tobacco smoke (ETS) from a prototype cigarette that primarily heats tobacco was compared to that of four popular commercially available cigarettes that burn tobacco. ETS was generated by six individuals simultaneously smoking 1
A rapid gas-liquid chromatographic method for the estimation of nicotine in plasma is described. Nicotine is extracted from alkalinized plasma into diethyl ether. This is then concentrated by evaporation and, after an acid back extraction is re-extracted into n-heptane (nitrogen detector) or
Hair samples were collected from 24 infants (3-36 months) exposed and non-exposed to environmental tobacco smoke. Hair was washed in dichloromethane, digested in NaOH, extracted by solid-phase extraction and analyzed by high-performance liquid chromatography to determine the content of nicotine and
We report a procedure for determining nicotine and cotinine in plasma. Nicotine is extracted from 1 ml of plasma with diethyl ether, back extracted, and analyzed by gas-liquid chromatography with a nitrogen/phosphorus detector. Nicotine and its internal standard, modaline, had retention times of 1.9
A method using reversed phase liquid chromatography-electrospray ionization-tandem mass spectrometry was developed for the determination of 52 pesticides in tobacco. The influence of mobile phase additives was investigated to improve sensitivity and accuracy of the method and to reduce matrix
ExtrelutR extraction and glass capillary gas chromatography were applied to the routine determination of nicotine and its metabolites cotinine, nicotine-1'-N-oxide and cotinine-1-N-oxide in urine and plasma. After extraction of nicotine and cotinine both N-oxides and phendimetrazine-N-oxide (used as
A highly sensitive and reliable method for the determination of nicotine and its metabolite cotinine in human plasma by high-performance liquid chromatography was developed. Nicotine and cotinine were extracted from alkalinized plasma with dichloromethane and the volatility of nicotine was prevented
OBJECTIVE
To develop a rapid method for determination of nicotine and its metabolite cotinine in human hair with capillary gas chromatography with flame ionization detector.
METHODS
The hair sample was digested by 1.5 mol/L sodium hydroxide solution. The nicotine and cotinine in the hair sample were
A fully automated multi-dimensional gas chromatography (MDGC) system with a megabore precolumn and cyclodextrin-based analytical column was developed to analyze the enantiomeric compositions of anatabine, nornicotine and anabasine in commercial tobacco. The enantiomer abundances of anatabine and
A practical method for analysis of residues of imidacloprid in baked tobacco leaves has been developed using HPLC with liquid-liquid partition clean-up. Imidacloprid was extracted with ethyl acetate under ultrasound, and cleaned up by liquid-liquid partition with 50 g litre(-1) aqueous sodium
A method was developed for rapid determination of 29 pesticide residues in tobacco based on gas chromatography coupled with electron impact ionization mass spectrometric detection (GC-EI/MS). After the optimization of different parameters, such as the extraction solvent, elution solvent, purificant,
A method of off-line combination of liquid chromatography and capillary gas chromatography-mass spectrometry (LC-CGC/MS) was established for the analysis of volatile and semi-volatile compounds in tobacco. The separation mechanism of volatile and semi-volatile compounds was studied. An LC column of
A method was developed for the efficient determination of nicotine and cotinine in rat plasma samples originating from nicotine exposure studies. Nicotine and cotinine were extracted from plasma samples with dichloromethane and concentrated to minimum volume with nitrogen stream. The volatility of