Computational Modeling of Aerosol Particle Transport through Lung Airway Mucosa

Abstract

Delivery of aerosols to the lung has great potential for the treatment of various lung diseases. However, the lungs are coated by a protective mucus layer whose complex properties make this form of delivery difficult. Mucus is a non-Newtonian fluid and is cleared from the lungs over time by ciliated cells. Further, its gel-like structure hinders the diffusion of particles through it. Any aerosolized treatment of lung diseases must have certain properties to circumvent the mucosal barrier, and these properties may vary between diseases, drugs, and patients. Using computational fluid dynamics, a model of this mucus layer was constructed to simulate the convective and diffusive transport of impacted aerosol particles. The model predicts the dosage fraction of particles of a certain size that penetrate the mucus and reach the underlying tissue, as well as the distance downstream of the dosage site where epithelial concentration is maximized. Reactions that may occur in solution are also considered, with simulated data for the interaction of a model virus and antibody. The model is modular so that various lung regions and patient health states may be simulated.