Thermal Desorption Aerosol Gas Chromatograph

Our thermal desorption aerosol gas chromatograph provides hourly, in-situ molecular speciation and quantitation of semi-volatile organic aerosols. Developed jointly with the University of California, Berkeley, this instrument is sold through Aerodyne Research, Inc.

How it works:

Ambient samples are collected into a thermal desorption cell. Once each hour the collected sample is heated, and the evolved gases transferred via a focusing trap to a gas chromatograph coupled to a mass spectrometer. Automated standards introduction provides quantitation for each sample.


  • Molecular level identification of organic marker compounds

  • Month long field deployments provide hourly resolved composition

  • Two sample collectors developed: (1) traditional, bounce-free impaction optimized for the least volatile species and (2) an all metal, passivated fiber filter optimized for collection of particle and semi-volatile vapors

  • Each sample is analyzed with a suite of internal standards for accurate quantification

  • The option of online derivatization enables highly polar compounds to be analyzed

Example Data

Berkeley atmospheric sample demonstrating the partitioning of simple hydrocarbons between the gas and particle phases as captured by the semi-volatile version of the TAG instrument.

Example organic tracer for atmospherically processed biogenic gas phase emissions measured by the TAG instrument in Amazonia, Brazil during the GoAmazon14/15 campaign.

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