AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Online Aerosol Monitoring for In Vitro Toxicological Studies Using Single-Photoionization Mass Spectrometry
CARLA FREGE, Sandro Steiner, Sandra Ferreira, Shoaib Majeed, Francesco Lucci, Mahdi Asgari, Julia Hoeng, Stefan Frentzel, Arkadiusz Kuczaj, Philip Morris International R&D
Abstract Number: 433 Working Group: Aerosol Exposure
Abstract Chemical and physical characterization of transported evolving aerosols in in vitro systems present a series of challenges, spanning from appropriate sampling ability of delivered aerosols through measurement capabilities of their properties to possibilities of performing online measurements of the compounds of interest in the flowing aerosol during exposure. In addition, when using mass spectrometry, high concentrations of compounds (in the range of parts per million) can saturate the detection system. Furthermore, the ionization method for detection of molecules of interest can produce fragmentation, making the analysis process more difficult. In this study, we used soft ionization mass spectrometry to measure the main compounds of e-cigarette aerosol online during in vitro exposure. A single-photoionization time-of-flight mass spectrometer (SPI-TOF-MS) (F. Mühlberger et al., 2002) was used to measure the chemical composition of the aerosol. The initial e-cigarette test liquid (e-liquid) was composed of propylene glycol and glycerol, nicotine, and water. Aerosol flow was driven by the standard operating procedure (55 ml puff volume in 3 seconds, 30-second frequency) using a programmable dual syringe pump (WHO TobLabNet SOP1, 2012), and measurements were performed by sampling undiluted and diluted test aerosol by mixing it with pure air, sampled in a transfer line through a capillary with a flow rate of 2–4 mL/min. The sample is ionized by a deuterium lamp, and ions are guided through a set of lenses, where they are detected according to their time of flight. The applied technique opens the possibility not only to quantify compounds of interest during exposure but also to perform detailed time resolution of delivered aerosol on a puff-by-puff basis. The system can be applied to monitor targeted compounds in a specific mass-to-charge range (40–200 m/z). Complementary measurements are ongoing to further investigate the application of SPI-TOF-MS for online monitoring of in vitro exposures.