AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Advances in Nanoparticle Sampling and Analysis Methods
GARY CASUCCIO, Traci Lersch, Henry Lentz, Dan Miller-Lionberg, John Volckens, RJ Lee Group, Inc.
Abstract Number: 402 Working Group: Aerosol Exposure
Abstract Collection, analysis, and speciation methods for engineered, naturally occurring, and incidental nanoparticles are needed to determine workplace and ambient exposures. Advances in sampling and analysis techniques in this ultra-fine size fraction have evolved for the measurement of nanoparticles. A portable thermophoretic sampler has been developed that deposits ultra-fine particles in the air directly onto an electron microscope (EM) grid. The sampler has high collection efficiencies for ultrafine particles and further, sample integrity is maintained because unlike filter-based sampling techniques, no sample preparation is needed prior to the EM analysis.
The sampled EM grids are inserted directly into a high resolution EM for examination of particle associations, composition, and concentrations. Manual examination using EM techniques can be used to distinguish particle phases and evaluate relationships such as agglomerated state verses unbound particles. Advances in automation of EMs can be applied for direct particle size measurements to obtain quantitative data on particle concentration and size distribution of the collected particles down to 20 nm.
Data from studies using samples collected with the thermophoretic sampler are illustrated and compared to results from both direct-reading instruments and from integrated air samples with a focus on identifying the advantages and limitations of this technology.