Generation and recovery of sub-micron diameter fibrous aerosols

In toxicology and industrial hygiene, fibrous aerosols have long been associated with health risks. Aerodynamic alignment with inhaled air streamlines allows long, cylindrical fibers to penetrate deep into the lung, whereas compact particles of similar mass are filtered out in the upper respiratory tract. For drug delivery applications, fibrous aerosols may thus enable a relatively large drug mass to be delivered to the distal regions of the lung. At present, the aerodynamic behaviors of fibers that influence deposition in the respiratory tract are discussed. Methods for generating monodisperse (in both diameter and length) fibrous aerosols and of tagging these aerosols with a UV absorbent material, both by physical vapor deposition, are outlined.