Principal-components analysis of fluorescence cross-section spectra from pathogenic and simulant bacteria

Principal-components analysis of a new set of highly resolved (<1 nm) fluorescence cross-section spectra excited at 354.7 nm over the 370-646 nm band has been used to demonstrate the potential ability of UV standoff lidars to discriminate among particular biological warfare agents and simulants over short ranges. The remapped spectra produced by this technique from Bacillus globigii (Bg) and Bacillus anthracis (Ba) spores were sufficiently different to allow them to be cleanly separated, and the Ba spectra obtained from Sterne and Ames strain spores were distinguishable. These patterns persisted as the spectral resolution was subsequently degraded in processing from ~1 to 34 nm. This is to the authorʹs knowledge the first time that resolved fluorescence spectra from biological warfare agents have been speciated or shown to be distinguishably different from those normally used surrogates by optical spectroscopy.