Rapid and chemically selective nicotine quantification in smokeless tobacco products using GC-MS.

In recent years, there has been a rapid proliferation of smokeless products with a wide range of nicotine content and flavoring formulations that may appeal to new users and existing cigarette smokers. The CDC nicotine method, which employs gas chromatography-flame ionization detection (GC-FID), provides a robust means for measuring nicotine in smokeless tobacco. However, several compounds, identified in a few flavored smokeless products, interfere with nicotine quantification using GC-FID. In response, the standard nicotine method (26.7 min run time) was modified to use faster GC ramping (3.7 min run time) and detection with mass spectrometry (GC-MS) in selected ion-monitoring mode to reduce signal interferences that can bias nicotine values. Seven conventional smokeless samples (n = 12) and blank tobacco samples spiked at three nicotine concentration levels (n = 5) were analyzed using the GC-FID and GC-MS methods and found to be in excellent agreement. However, only the GC-MS method provided confirmation of chromatographic peak purity in certain highly flavored products. The GC-MS method is not intended to replace the GC-FID method but to provide a method versatile enough to analyze a wide range of nicotine values in domestic and international samples of varying complexity. Accurate nicotine quantification is important for determining total nicotine content in tobacco and in subsequent calculations of un-protonated nicotine content.