Accession Number:

ADA379175

Title:

Single-Shot Fluorescence Spectra of Individual Micrometer-Sized Bioaerosols Illuminated by a 351- or a 266-nm Ultraviolet Laser

Descriptive Note:

Journal article

Corporate Author:

YALE UNIV NEW HAVEN CT DEPT OF APPLIED PHYSICS

Personal Author(s):

• Pan, Yong-le
• Holler, Stephen
• Chang, Richard K.
• Hill, Steven C.
• Pinnick, Ronald G.
• Niles, Stanley
• Bottiger, Jerold

Report Date:

1999-01-15

Pagination or Media Count:

4.0

Abstract:

Reproducible fluorescence spectra of individual 2 to 5 micrometers diameter biological aerosol particles excited with a single shot from a Q-switched laser 266 or 351 nm have been obtained with highly improved signal-to- noise ratios. Critical to the advance are crossed diode-laser trigger beams, which precisely define the sample volume, and a reflecting objective, which minimizes chromatic aberration and has a large N.A. for collecting fluorescence. Several allergens red oak, meadow oat pollen, paper mulberry pollen, and puffball spores have different fluorescence spectra. Bacillus subtilis fluorescence spectrum deteriorates at high 266-nm incident intensity. Dry riboflavin particles illuminated with a 351-nm light exhibit a new 420-nm fluorescence peak that grows nonlinearly with laser pulse energy.

Descriptors:

• *BIOLOGICAL AEROSOLS
• *FLUORESCENCE
• BACILLUS SUBTILIS
• DIODE LASERS
• EXCITATION
• LIGHT SCATTERING
• PARTICLE SIZE
• PULSED LASERS
• Q SWITCHING
• REPRINTS
• SIGNAL TO NOISE RATIO
• SPECTRA
• ULTRAVIOLET LASERS

Subject Categories:

• Chemical, Biological and Radiological Warfare
• Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE