title: Size-Limited Penetration of Nanoparticles into Porcine Respiratory Mucus after Aerosol Deposition.
abstract: We investigated the rheological properties and the penetration of differently sized carboxylated nanoparticles in pig pulmonary mucus, on different distance and time scales. Nanoparticles were either mechanically mixed into the mucus samples or deposited as an aerosol, the latter resembling a more physiologically relevant delivery scenario. After mechanical dispersion, 500 nm particles were locally trapped; a fraction of carboxylated tracer particles of 100 or 200 nm in diameter could however freely diffuse in these networks over distances of approximately 20 μm. In contrast, after aerosol deposition on top of the mucus layer only particles with a size of 100 nm were able to penetrate into mucus, suggesting the presence of smaller pores at the air-mucus interface compared to within mucus. These findings are relevant to an understanding of the fate of potentially harmful aerosol particles, such as pathogens, pollutants, and other nanomaterials after incidental inhalation, as well as for the design of pulmonary drug delivery systems.
authors.forename: Xabier
authors.initials: X
authors.lastname: Murgia
authors.affiliation: Institute for Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology (KIT) , 76131 Karlsruhe, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Pawelzyk
authors.forename: Ulrich F
authors.initials: UF
authors.lastname: Schaefer
authors.forename: Christian
authors.initials: C
authors.lastname: Wagner
authors.affiliation: Institute for Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology (KIT) , 76131 Karlsruhe, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Willenbacher
authors.forename: Claus-Michael
authors.initials: CM
authors.lastname: Lehr
mesh_terms: D000336:Aerosols / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D004337:Drug Carriers / Q000378:metabolism*; D008168:Lung / Q000378:metabolism*; D009093:Mucus / Q000378:metabolism*; D053758:Nanoparticles / Q000378:metabolism*; D010316:Particle Size; D020545:Respiratory Mucosa / Q000166:cytology / Q000187:drug effects*; D012212:Rheology; D013552:Swine
chemical_list: D000336:Aerosols; D004337:Drug Carriers