Nicotine Quantification In Vitro: A Consistent Dosimetry Marker for e-Cigarette Aerosol and Cigarette Smoke Generation

Abstract

The e-cigarette category is evolving rapidly, providing consumers with a variety of formats, ranging from cig-alike products to larger, high-powered modular devices. When generating an in vitro assessment approach across such diverse products, dosimetry considerations are paramount. In this article, we have compared nicotine quantification techniques in two studies using a Vitrocell VC 10 Smoking Robot to generate aerosols from different ecigarettes. In Study 1, a 3R4F reference cigarette and four different commercially available e-cigarettes were compared: puff-by-puff nicotine concentration was quantified at the same e-cigarette puffing regime (CRM No81) or with different puff durations, (2 or 3 seconds), comparing 3R4F puff-by-puff yields following ISO and HCI smoking regimes. In Study 2, 3R4F and one e-cigarette were assessed for puff-by-puff nicotine concentration in different locations (China and United Kingdom) comparing different nicotine quantification methods with gas chromatography-mass spectrometry and UPLC-MS/MS used in the two laboratories. Study 1 showed that 3R4F cigarette delivers different nicotine concentrations across the different regimes and puff number, supporting the nicotine methodology; e-cigarettes tested generated different amounts of nicotine across the devices tested, but showed consistent puff-by-puff delivery per device. Study 2 showed positive agreement between results across two different laboratories utilizing different methods for nicotine quantification; statistical analysis, combining all interlaboratory variables, indicated that laboratory differences and the interaction of laboratory and puff number were not significant (p = 0.067 and 0.960, respectively). These studies will add further knowledge to support the in vitro assessment of novel nicotine products, providing reliability and assurance in the area of in vitro dosimetry.

The in vitro assessment of a novel vaping technology

“…The amounts of nicotine in test product AqE and in the basal media of WA-exposed cells were quantified as previously described [ 30 ]. Briefly, 990 μL sample was spiked with 10 μL of 1 mg/mL nicotine-d4.…”

“…The solvent was removed using a rotary concentrator, and residue was resuspended in 1 mL 5% v/v acetonitrile: water, shaken, vortexed and centrifuged. 0.5 mL was then removed for analysis by ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS; [ 30 ]).…”

A Case Study for the Comparison ofIn VitroData Across Multiple Aerosol Exposure Studies with Extrapolation to Human Dose

“…Dosimetry approaches have been used to characterize the exposure setup, define exposure conditions, and measure exposure for quality control and to compare exposure systems between laboratory studies. 18,[25][26][27] The use of dosimetry approaches alongside in vitro aerosol exposures has increased significantly in recent years, in both terms of application and sophistication. The environment has evolved from simple gravimetric measurement of particulate deposition through fluorometric analysis 19,28 into the use of specialized aerosol particle size and concentration measurement tools.…”

Invited review: human air-liquid-interface organotypic airway tissue models derived from primary tracheobronchial epithelial cells—overview and perspectives

“…To adapt the conventional smoking robots for e-cig research, Vitrocell® VapeStarters are used for activating various ecig products and, therefore, have greatly expanded the range of tobacco products that can be tested with the systems. Aerosol deposited mass per puff as well as nicotine and carbonyl concentrations are commonly used for e-cig dosimetry measurement (Adamson et al 2017;Iskandar et al, 2019;Bishop et al 2019).…”