ABSTRACT
Background
The free base and protonated nicotine forms in e-cigarette aerosol have shown different absorption profiles in users. Therefore, it is also important to identify the factors which can affect the ratio of these nicotine forms in the aerosol. Such factors may include nicotine concentrations, flavors, PG:VG ratios, types of nicotine chemical compounds and e-cigarette battery power outputs. The current study attempts to identify such factors using a controlled experiment.
Research designs and methods
The aerosol was generated using validated aerosol generating model. Various factors were tested for their effect on nicotine forms. Additionally, a degradation study of one of the nicotine compounds, nicotine salicylate, was also carried out using mass spectrometry.
Results
The free base nicotine in the aerosol was found to be affected by flavors, battery power output, nicotine compound type and PG:VG ratios. Based on the preliminary mass spectrometry data, degradation of nicotine salicylate was found to be one of the significant factors affecting free base nicotine in aerosol.
Conclusions
Potential factors affecting free base nicotine in e-cigarette aerosol have been identified in this study. These findings would help in understanding the nicotine delivery better and assist for better regulations.
Acknowledgments
The authors would also like to thank Chemnovatic, Poland for providing nicotine salts for the analysis. The authors would also like to thank Dr. Leon Kosmider for his valuable guidance in building the Aerosol Generating Model.
Reviewer disclosures
Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.
Abbreviations
NA Not Applicable
Nicfree base nicotine
NicH+protonated nicotine
e-cig electronic cigarette
PG Propylene Glycol
VG Vegetable Glycerin
Declaration of interest
Vinit Gholap is a graudate student funded by VCU school of Pharmacy and Virginia Youth Tobacco Projects Small Grants Program. Matthew Halquist was funded as the PI of the Bioanalytical Core Laboratory, The Central Virginia Center on Drug Abuse Research, NIDA, 2P30DA033934-06 and Virginia Youth Tobacco Projects Small Grants Program. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
Author contributions
Vinit Gholap and Matthew Halquist were involved in the conception, design and analysis of the data and drafting the paper. Adam Pearcy has significantly contributed in interpretation of the data and critically reviewing the manuscript. All authors have approved the final version of the paper for publication.