IngentaConnect Development of Size-Selective Sampling of Bacillus anthracis Surr...

Authors: Gibb-Snyder, Emily¹; Gullett, Brian¹; Ryan, Shawn¹; Oudejans, Lukas²; Touati, Abderrahmane²

Source: Applied Spectroscopy, Volume 60, Issue 8, Pages 196A-216A and 833-950 (August 2006) , pp. 860-870(11)

Publisher: Society for Applied Spectroscopy

Abstract:

Size-selective sampling of Bacillus anthracis surrogate spores from realistic, common aerosol mixtures was developed for analysis by laser-induced breakdown spectroscopy (LIBS). A two-stage impactor was found to be the preferential sampling technique for LIBS analysis because it was able to concentrate the spores in the mixtures while decreasing the collection of potentially interfering aerosols. Three common spore/aerosol scenarios were evaluated, diesel truck exhaust (to simulate a truck running outside of a building air intake), urban outdoor aerosol (to simulate common building air), and finally a protein aerosol (to simulate either an agent mixture (ricin/anthrax) or a contaminated anthrax sample). Two statistical methods, linear correlation and principal component analysis, were assessed for differentiation of surrogate spore spectra from other common aerosols. Criteria for determining percentages of false positives and false negatives via correlation analysis were evaluated. A single laser shot analysis of approximately 4 percent of the spores in a mixture of 0.75 m³ urban outdoor air doped with approximately 1.1 × 10⁵ spores resulted in a 0.04 proportion of false negatives. For that same sample volume of urban air without spores, the proportion of false positives was 0.08.

Keywords: LASER-INDUCED BREAKDOWN SPECTROSCOPY; LIBS; BIOLOGICAL AGENT AEROSOL; BIOAEROSOL COLLECTION; SPORE DETECTION

Document Type: Research article

DOI: 10.1366/000370206778062192

Affiliations: 1: U.S. Environmental Protection Agency (E305-01), Office of Research and Development, Research Triangle Park, North Carolina 27711 2: Arcadis G&M Research, P.O. Box 13109, Triangle Park, North Carolina 27709

Your trusted access to this article has expired.

The full text electronic article is available for purchase. You will be able to download the full text electronic article after payment.

$29.00 plus tax Refund Policy

Development of Size-Selective Sampling of Bacillus anthracis Surrogate Spores from Simulated Building Air Intake Mixtures for Analysis via Laser-Induced Breakdown Spectroscopy