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1.
J Agric Food Chem ; 55(4): 1097-102, 2007 Feb 21.
Article in English | MEDLINE | ID: mdl-17256957

ABSTRACT

A simple, rapid, and sensitive assay of nicotine in tobacco has been developed using pyrolysis-gas chromatography-mass spectrometry (DSP-GC-MS). The optimum pyrolyzer (desorption) conditions, using Korean tobacco grade B1O (0.4 mg) and n-heptadecane as an internal standard, were found to be heating from 50 to 300 degrees C at a rate of 60 degrees C/min. Replicate determinations (n = 5), on the same tobacco and using n-heptadecane as the internal standard, resulted in a nicotine content of 1.96%, with a relative standard deviation (RSD) of 1.9%. This result was in good agreement with those from established methods: the Cai ether extraction method, a chloroform extraction method, and the CORESTA recommended method. However, the DSP method requires less than half the time of the solvent extraction methods, requires less sample, is almost solvent-free, and is less labor-intensive. The DSP method was used to determine the nicotine content of eight flue-cured tobaccos from Brazil, China, Korea, and the United States, which were found to have contents ranging from 1.21 to 2.19%.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Nicotiana/chemistry , Nicotine/analysis , Chloroform , Hot Temperature , Plant Leaves/chemistry
2.
J Chromatogr A ; 1089(1-2): 227-34, 2005 Sep 30.
Article in English | MEDLINE | ID: mdl-16130791

ABSTRACT

The optimum conditions for the analysis of the volatile organic components of pine needles from Pinus densiflora using double-shot pyrolysis-gas chromatography-mass spectrometry (DSP-GC-MS) were investigated with respect to thermal desorption temperature and duration of heating. A total of 41 compounds were identified using thermal desorption temperatures of 150 degrees C, 200 degrees C, 250 degrees C and 300 degrees C. Thermal decomposition products, which include acetol, acetic acid, furfurals and phenols, were observed only at thermal desorption temperatures exceeding 250 degrees C: they were not observed in the extract from a simultaneous distillation extraction (SDE) method. Heating times of 1 s, 6 s, 30 s, 150 s and 300 s were investigated at the thermal desorption temperature of 200 degrees C, whence it was found that thermal decomposition products were produced only at heating times over 30 s. The optimum pyrolyzer conditions for the analysis of pine needles using DSP-GC-MS is 200 degrees C for 6 s. Under these conditions, this method gives comparable results to the SDE method.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Pinus/chemistry , Plant Leaves/chemistry , Volatilization
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