Detection of biological aerosols by luminescence techniques

✍ Scribed by Peter J. Stopa; Darlene Tieman; Philip A. Coon; Maurice M. Milton; Dorothea Paterno

• Publisher: John Wiley and Sons
• Year: 1999
• Weight: 93 KB
• Volume: 3
• Category: Article
• ISSN: 1086-900X
• DOI: 10.1002/(sici)1520-6521(1999)3:4/5<283::aid-fact7>3.0.co;2-9

✦ Synopsis

Luciferin-luciferase (LL) luminescence techniques were used to successfully measure the adenosine triphosphate (ATP) content (pg/ml) in aerosol samples containing either vegetative bacterial cells or spores. Aerosols were collected with wet or dry sampling devices. Evaluation for the presence of total biomass from both bacterial and nonbacterial sources of ATP was achieved by suspending the collected aerosol samples in phosphate-buffered saline (PBS), using a pipette to draw off a 50-l aliquot of the PBS suspension into a Filtravetteீ, and then adding bacterial releasing agent (BRA). The sample was then reacted with LL, and the resulting relative luminescence units (RLUs), indicative of the total ATP content, were measured. Identical techniques were used to prepare the bacterial cells for analysis with one additional step: a wash with somatic cell releasing agent (SRA) before adding BRA. This step removes interfering substances or nonbacterial sources of ATP. For spore analysis, an equivolume sample of the PBS suspension was added to an equivolume of trypticase soy broth (TSB), incubated at 37 ؇C for 15 min, and processed using methods identical to bacterial cell analysis. With the use of these techniques we were able to detect Bacillus subtilis variation niger, formerly known as Bacillus globigii (BG) in artificially inoculated aerosol samples at concentrations Ն 10 5 colony-forming units (CFU) per milliliter. Results of field and chamber trials *The use of any products or trade names does not imply endorsement by the U.S. Army, Department of Defense, or any other government agency. The opinions stated in this article are those of the authors and do not reflect any official opinions of the Department of the Army or any other agency of the U.S. government.