Spectrally-resolved fluorescence cross sections of aerosolized biological live agents and simulants using five...

A system for measuring spectrally-resolved fluorescence cross sections of single bioaerosol particles has been developed and employed in a biological safety level 3 (BSL-3) facility at Edgewood Chemical and Biological Center (ECBC). It is used to aerosolize the slurry or solution of live agents and surrogates into dried micron-size particles, and to measure the fluorescence spectra and sizes of the particles one at a time. Spectrally-resolved fluorescence cross sections were measured for (1) bacterial spores: Bacillus anthracis Ames (BaA), B. atrophaeus var. globigii (BG) (formerly known as Bacillus globigii), B. thuringiensis israelensis (Bti), B. thuringiensis kurstaki (Btk), B. anthracis Sterne (BaS); (2) vegetative bacteria: Escherichia coli (E. coli), Pantoea agglomerans (Eh) (formerly known as Erwinia herbicola), Yersinia rohdei (Yr), Yersinia pestis CO92 (Yp); and (3) virus preparations: Venezuelan equine encephalitis TC83 (VEE) and the bacteriophage MS2. The excitation wavelengths were 266 nm, 273 nm, 280 nm, 365 nm and 405 nm.