AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Evaluating Bioaerosol Transport Using Unique DNA-Barcoded Aerosol Test Particles and Passive Sampling
Ruth N. Udey, Elizabeth K. Wheeler, A. Daniel Jones, GEORGE R. FARQUAR, Lawrence Livermore National Laboratory
Abstract Number: 46 Working Group: Bioaerosols: Characterization and Environmental Impact
Abstract Aerosol transport monitoring is important for detecting the presence of airborne contaminants and tracking their fate in populated environments where they may adversely affect human health. We have developed novel aerosol test particles containing DNA barcodes for evaluating aerosol transport that are customizable and safe for human exposure. The generation methods enabled size tuning of the particles to accurately mimic bioaerosols. The addition of different DNA molecules as unique particle identifiers created distinctive particle types for detection of simultaneous or sequential aerosol releases in the same test environment. These customizable aerosol test particles will provide vital experimental feedback for evaluating atmospheric and particle transport models in populated environments.
Saccharide food additives approved by the FDA for human exposure (e.g. maltodextrin) were the bulk materials for these novel test particles. The non-coding DNA barcodes were also safe for human contact and yielded customized test particles specifically detected using quantitative real-time polymerase chain reaction (QRT-PCR) assays. A commercial spray dryer was used to generate the test particles in gram-scale quantities, and the resulting particle size-distributions were tunable between 1 and 10 micrometers by varying solution concentrations and production parameters.
These aerosol test particles were successfully aerosolized, collected, and detected using QRT-PCR during several atmospheric release tests. Particles were collected actively on filters using dry filter unit aerosol samplers, as well as passively on common materials, including glass slides, paper, and cotton t-shirts. Passive sampling provided alternate aerosol collection methods that prevented building airflow alteration, which was observed when active sampling methods were employed.
Prepared by LLNL under Contract DE-AC52-07NA27344.