AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Recent Applications of Single Particle Aerosol Mass Spectrometry (SPAMS)
DAVID FERGENSON, Anna Susz, David Kohler, Jia-Yih Feng, Jordon Rose, Maria Balaxi, Bradley D. Morrical, Payam Nahid, Midori Kato-Maeda, Adithya Cattamanchi, Livermore Instruments Inc.
Abstract Number: 350 Working Group: Instrumentation and Methods
Abstract Single Particle Aerosol Mass Spectrometry (SPAMS) measures the aerodynamic diameter and chemical composition of individual aerosol particles sampled directly from the environment in real-time. In a SPAMS instrument, individual particles are drawn through several stages of differential pumping after which they cross a square profile, continuous wave laser and an adjacent pulsed, high powered ionization laser. The transit time of the particle across the continuous wave laser is used to compute its velocity and thus its aerodynamic diameter. The pulsed laser generates ions from the chemical constituents of the particle and those ions are analyzed by a dual-polarity time-of-flight mass spectrometer. A Livermore Instruments SPAMS 3.0 analyzes up to 250 particles per second in this manner with the added advantage of being able to analyze particles over a broad range of sizes, ranging from 0.1 micrometers to at least 8 micrometers in aerodynamic diameter.
Two recent applications of the SPAMS 3.0 will be discussed: The analysis of inhaled pharmaceuticals and the real-time detection of mycobacteria. SPAMS analyses performed on a commercial formulation of indacaterol demonstrated analytical consistency in repeated measurements carried out over a 2-week period. The particle size distribution of aerosolized ciprofloxacin determined using SPAMS analysis was compared with cascade impaction data to enable scaling between SPAMS and the standard regulatory and pharmacopeial approach of using Next Generation Impactor analyses coupled with high performance liquid chromatography. In a separate series of experiments, several strains of M. tuberculosis were analyzed, with pathogen-specific marker peaks detected in all.