Characterization of Particle Losses in an Inhalation Exposure System
Amina Moheyuddin
Mentors: Loyda Mendez & Robert Phalen
Nose-only exposure systems are used to deliver aerosols into the respiratory tract of experimental
animals. Characterization of particle losses on nose ports is necessary in order to efficiently deliver a
pre-determined aerosol concentration to the animals’ breathing zone. It was hypothesized that the
particle losses in the system would be dependent on particle size. To characterize the particles losses
on the nose ports, I aerosolized a liquid suspension containing fluorescent polystyrene latex
microspheres of three different diameters through the exposure system. Then the particles deposited
on the nose ports were extracted by sonication and colleted on nucleopore filters. The filters were
examined under a fluorescent microscope, and the number of particles deposited per nose port was
calculated. The results supported the hypothesis and showed that the particle losses were dependent
on particle size. The information gathered in this project is essential for proper experimental design
of inhalation studies.