Analyzing SPARTAN filters with an Aerosol Mass Spectrometer

Analyzing SPARTAN filters with an Aerosol Mass Spectrometer Rachel O’Brien, Kelsey Ridley, Jesse Kroll Department of Civil and Environmental Engineering, MIT Manjula Canagaratna, John Jayne, Philip Croteau, Aerodyne Research, Inc. June 9, 2015

High Resolution-TOF-AMS • Aerosol Mass Spectrometer with a Time of Flight mass spectrometer • Measure refractory aerosol species • Resolution ~ 2 -3 k m/Dm

AMS studies worldwide… costly deployment, few long term data sets organic sulfate nitrate ammonium Zhang et al. , 2007

Filters and off-line analysis • Global filter networks long term data sets, lower deployment cost, more remote and difficult locations • Filter extracts small sample volumes

Small Volume Nebulizer (SVN) design AMS Clean house air Kapton Polyimide film Ultrasonic transducer Minimum concentration ~0. 15 g L-1 (20 -30 mg into ~100 m. L to be above LOD)

SVN Good correlation with commercial atomizer TSI Atomizer

ACSM AMS m/z Filter extract (ACSM) Normalize relative intensity Inter-instrument comparison Filter extract (AMS)

HR-MS from Bandung, Indonesia: August 19 -20, 2014 O/C = 0. 6 Org/SO 4 = ~6 Org SO 4 NO 3 NH 4

Future development • Continuous injection AMS • Add automation, improve sensitivity • Addition of internal standard • Mass quantification • Orthogonal analyses– UV/Vis, fluorescence, etc. Syringe pump

Conclusions • The SVN can be used to generate AMS spectra from SPARTAN filters: • Ensemble organic composition, O/C • Need > 20 -30 mg of sample • Extract filters in water • Ongoing development to improve utility of the SVN: • Quantification • Increased sensitivity • Orthogonal analyses

Acknowledgments • Kelsey Ridley, Jesse Kroll and the Kroll group • Manjula Canagaratna, John Jayne, Philip Croteau, and Aerodyne Research, Inc.