Condensational particle growth device for reliable cell exposure at the air–liquid interface to nanoparticles

Abstract

A first-of-its-kind aerosol exposure device for toxicity testing, referred to as the Dosimetric Aerosol in Vitro Inhalation Device (DAVID), was evaluated for its ability to deliver airborne nanoparticles to lung cells grown as air–liquid interface (ALI) cultures. For inhalation studies, ALI lung cell cultures exposed to airborne nanoparticles have more relevancy than the same cells exposed in submerged culture because ALI culture better represents the respiratory physiology and consequently more closely reflect cellular response to aerosol exposure. In DAVID, water condensation grows particles as small as 5 nm to droplets sized >5 µm for inertial deposition at low flow rates. The application of DAVID for nanotoxicity analysis was evaluated by measuring the amount and variability in the deposition of uranine nanoparticles and then assessing the viability of ALI cell cultures exposed to clean-air under the same operational conditions. The results showed a low coefficient of variation, <0.25, at most conditions, and low variability in deposition between the exposure wells, trials, and operational flow rates. At an operational flow rate of 4 LPM (liter per minute), no significant changes in cell viability were observed, and minimal effects observed at 6 LPM. The reliable and gentle deposition mechanism of DAVID makes it advantageous for nanoparticle exposure.

Copyright © 2019 American Association for Aerosol Research

Acknowledgments

The authors would like to thank the Student Research Participation Program at the U.S. Air Force Research Laboratory, 711th Human Performance Wing, Airman Systems Directorate, Bioeffects Division, Molecular Mechanisms Branch administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. DOE and USAFRL for the support of this work. Special thanks to Drs. Chelsey Simmons and Hugh Fan for research guidance and use of their oxygen plasma treater and UV sterilization devices for the custom cell platforms.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was funded by the UF College of Engineering Institute for Networked Autonomous Systems (INAS) Fellowship, UF University Scholars Program, National Institutes of Health [Grant nos. R21AI123933 and 1R43ES030649].