Separating hazardous aerosols from ambient aerosols: role of fluorescence-spectral determination, aerodynamic deflector and pulse aerodynamic localizer (PAL)

An aerosol deflection technique based on the single-shot UV-laser-induced fluorescence spectrum from a flowing particle is presented as a possible front-end bio-aerosol/hazardous-aerosol sensor/identifier. Cued by the fluorescence spectra, individual flowing bio-aerosol particles (1-10 um in diameter) have been successfully deflected from a stream of ambient aerosols. The electronics needed to compare the fluorescence spectrum of a particular particle with that of a pre-determined fluorescence spectrum are presented in some detail. The deflected particles, with and without going through a funnel for pulse aerodynamic localization (PAL), were collected onto a substrate for further analyses. To demonstrate how hazardous materials can be deflected, TbCl 3 ⋅6H 2 O (a stimulant material for some chemical forms of Uranium Oxide) aerosol particles (2 μm in diameter) mixed with Arizona road dust was separated and deflected with our system.