Aerosol fluorescence spectrum analyzer for individual airborne biological particles

摘要

Abstract: We report the operation of an aerosol analyzer capable of measuring the fluorescence spectra of single micrometer-size bioaerosol particles. Aerosol particles in an air stream initially transverse a cw 488-nm 'trigger' laser beam where their elastic scattering and total fluorescence is measured with photomultipliers. When the elastic scattering and fluorescence signals meet certain criteria, a UV (266 nm) 'probe' laser is triggered and it illuminates the selected particles. The UV laser-excited spectra of particles are measured with the instrument's image-intensified CCD detector, gaged with signals from the trigger laser. We demonstrate the ability of the instrument to capture the fluorescence of single airborne biological particles. The results suggest that it may be possible to differentiate among biological particles based on their single particle fluorescence spectra. !21