Field test results of atmospherically dispersed vegetative cells for a tracer using a solar blind fluorescence LIDAR

Conference · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6588321

Karl, Jr, R R

A solar-blind ultraviolet (uv) LIDAR system has been assembled, tested, and calibrated for the remote detection of atmospherically dispersed biological particles released from an aerosol generator. Fluorescence excited by uv photons and emitted by the aromatic amino acids tryptophan, phenylalamine, and tyrosine indicates the presence of bacterial particles in the cloud. The high fluorescence cross section from 240 to 290-nm excitation results in strong emission in the solar blind region for the vegetative cells of Bacillus globiggi (BG) and Bacillus thuringinesis (BT). These bacteria, both as spores and as vegetative cells, have an absorption ideally located for remote excitation by the powerful, low divergence KrF excimer laser operating at 248 nm. Bacterial proteins have been observed as very dilute atmospheric aerosols to a range slightly greater than 1 km with a single laser shot. In a calibrated field test, we demonstrated detection of 0.3 Bacillus globiggi spore aerosol particles per cubic centimeter of air at a range of 1200 m with a ten-shot signal-to-noise ratio of better than 3:1. Other experiments with the BG and BT vegetative cells at Los Alamos have shown that the vegetative cells have even higher fluorescence cross sections and greater range sensitivities due to their increased size and farther uv shifted fluorescence compared to the spores. 3 figs.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6588321
• Report Number(s): LA-UR-88-3316; CONF-890133-2; ON: DE89002051
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AEROSOL GENERATORS
AEROSOLS
AMINO ACIDS
ATMOSPHERIC CIRCULATION
BACILLUS
BACTERIA
BIOLOGICAL INDICATORS
BIOLOGICAL MARKERS
CARBOXYLIC ACIDS
COLLOIDS
DETECTION
DISPERSIONS
EXCIMER LASERS
FIELD TESTS
FLUORESCENCE
GAS LASERS
ISOTOPE APPLICATIONS
KRYPTON FLUORIDE LASERS
LASERS
LUMINESCENCE
MICROORGANISMS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PROTEINS
SOLS
TESTING
TRACER TECHNIQUES