Abstract: A method for determining tobacco-specific nitrosamines (TSNAs) in cigarette smoke using one-step clean-up coupled with LC-MS/MS is provided, including the following steps: collecting a particulate matter of mainstream cigarette smoke with a Cambridge filter pad, mixing the particulate matter of mainstream cigarette smoke, an internal standards solution and water in a 50 mL plastic centrifuge tube, and vortexing the resulting mixture at room temperature to allow extraction; transferring an extraction solution after filtration to a new centrifuge tube, adding dichloromethane, and vortexing the resulting mixture; centrifuging to collect a dichloromethane extraction solution in a lower layer to another centrifuge tube, and placing the centrifuge tube in a water bath to remove dichloromethane; dissolving the resulting extraction solution in water, and transferring the resulting solution to an autosampler vial for LC-MS/MS analysis.

Abstract: A method for determining tobacco-specific nitrosamines (TSNAs) in tobacco using one-step clean-up coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) is provided, including the following steps: destemming flue-cured tobacco or sun-cured tobacco, drying, milling, and passing through a sieve; mixing the resulting tobacco, an internal standards solution and water in a plastic centrifuge tube, and vortexing the resulting mixture at room temperature to allow extraction; transferring an extraction solution after filtration to a new centrifuge tube, adding dichloromethane, and vortexing the resulting mixture; centrifuging to collect a dichloromethane extraction solution in a lower layer to another centrifuge tube, and placing the centrifuge tube in a water bath to remove dichloromethane; dissolving the resulting extraction solution in water, and transferring the resulting solution to an autosampler vial for LC-MS/MS analysis.

Abstract: A method for quantitatively analyzing 11 amide alkaloids in tobacco leaves using gas chromatography-tandem mass spectrometry, comprises: soaking with a sodium hydroxide solution so as to free amide alkaloids from a tobacco powder sample matrix, transferring target compounds into an ether layer through extraction with methyl tertiary butyl ether, concentrating methyl tertiary butyl ether extraction liquids for analysis with gas chromatography-tandem mass spectrometry, inputting chromatographic peak areas obtained by an instrument into standard calibration curve fitting equations of the corresponding amide alkaloids to obtain the concentrations of the corresponding target compounds, and converting the concentrations to obtain the contents of the corresponding amide alkaloids in the tobacco leaves. The method can quantitatively analyze the 11 amide alkaloids at the same time, and has the advantages of simpleness, rapidness, stability and the like.

Abstract: A method for identifying converters from tobacco seedling population. The method includes: 1) sowing and cultivating tobacco seeds to be identified for 45-55 days; sampling a plurality of leaf disks from each of 45-55 days old seedlings; 2) incubating the plurality of leaf disks of each seedling in a sealed container at 37° C. for 10-12 hours, thereby obtaining a plurality of incubated tobacco leaves of each seedling; 3) immersing the plurality of incubated tobacco leaves of each seedling in an extractant, extracting alkaloids and obtaining an extract of each seedling; 4) analyzing the amounts of nicotine and nornicotine in the alkaloids extract of each seedling; and 5) automatically recognizing peaks of the alkaloids extract of each seedling, and calculating the percent nicotine conversion (PNC) and the pseudo percent nicotine conversion (PPNC).

Abstract: A method for identifying converters from tobacco seedling population. The method includes: 1) sowing and cultivating tobacco seeds to be identified for 45-55 days; sampling a plurality of leaf disks from each of 45-55 days old seedlings; 2) incubating the plurality of leaf disks of each seedling in a sealed container at 37° C. for 10-12 hours, thereby obtaining a plurality of incubated tobacco leaves of each seedling; 3) immersing the plurality of incubated tobacco leaves of each seedling in an extractant, extracting alkaloids and obtaining an extract of each seedling; 4) analyzing the amounts of nicotine and nornicotine in the alkaloids extract of each seedling; and 5) automatically recognizing peaks of the alkaloids extract of each seedling, and calculating the percent nicotine conversion (PNC) and the pseudo percent nicotine conversion (PPNC).