DOI
https://doi.org/10.25772/FXT4-9M80
Defense Date
2017
Document Type
Dissertation
Degree Name
Doctor of Philosophy
Department
Pharmaceutical Sciences
First Advisor
Matthew S. Halquist
Abstract
Tobacco-specific nitrosamines (TSNA) are carcinogenic constituents derived from alkaloids in tobacco. Researchers are actively exploring several avenues to reduce TSNA levels in tobacco products like moist snuff tobacco. The focus of the research presented within is the quantitative analysis of TSNA in tobacco, specifically N’-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1(3-pyridyl)-1-butanone (NNK), N’-nitrosoanatabine (NAT), and N’-nitrosoanabasine (NAB).
Tobacco alkaloids and nitrosamines in tobacco are currently analyzed by different instrumentation due to orders of magnitude difference in their concentrations, chromatographic separation challenges due to structural similarities, and similar mass fragmentation patterns. An analytical column using silica and 1,2-bis(siloxy)ethane hybrid particles of 1.7 µm size is the foundation of a chromatographic separation of NNN, NNK, NAT, NAB, nicotine, nornicotine, anatabine, and anabasine. This is the first rapid and robust quantitative method for the TSNA and their alkaloid precursors using high pH mobile phase conditions with ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The suitability of the method is demonstrated by its application to the analysis of reference tobacco materials for cigarettes and moist snuff. In addition, a novel TSNA analytical method was developed using TSNA-specific molecularly imprinted polymers (MIP) as the selective extraction element from tobacco extract. The affinity mechanisms between MIP and TSNA were found to have extensive cross-reactivity to structurally similar alkaloids present in tobacco extract. TSNA-specific MIP was demonstrated to have stronger retention for the alkaloids than for the TSNA substrate. The MIP-TSNA interaction was optimized to create the first analytical method to quantify underivatized NNN and NNK from tobacco extracts by HPLC-UV.
Rights
© The Author
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
12-13-2017