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Chemistry LibreTexts

Mass Spectrometry – DESI vs DART

  • Page ID
    288218
  • Learning Objectives:

    After completing this unit on FSCV, a student will be able to use primary literature to:

    1. Analyze how instrumentation is described.
    2. Practice interpretation of mass spectrometric data analysis.
    3. Predict applications of mass spectrometric techniques.

    This unit uses three articles from the literature:

    1. Z. Takáts, J. M. Wiseman, B. Gologan, R. G. Cooks, “Mass Spectrometry Sampling Under Ambient Conditions with Desorption Electrospray Ionization,” Science, 2004, 306, 471-473.
    2. Z. Takáts, J. M. Wiseman, R. G. Cooks, “Ambient Mass Spectrometry Using Desorption Electrospray Ionization (DESI): Instrumentation, Mechanisms and Applications in Forensics, Chemistry, and Biology,” J Mass Spec, 2005, 40, 1261-1275.
    3. R. B. Cody, J. A. Laramée, and H. D. Durst, “Versatile New Ion Source for the Analysis of Materials in Open Air under Ambient Conditions,” Anal Chem, 2005, 77, 2297-2302.

     

     

     

    Name:_____________________________________                       

    DART versus DESI – A Primary Literature Analysis

     

     

    1. What is it?

     

    DART

    DESI

    Define the technique.

     

     

     

    Where is it developed? (Does this matter?)

     

     

     

     

     
    1. How does it work?

     

    DART

    DESI

    In your own words, describe how the instrumentation works.

     

     

     

    Describe how the ions are formed. Are there subtypes?

     

     

    Draw a schematic of the ionization system

     

     

     

     

     

    Both DESI and DART use components of other mass spectrometric techniques. Make a list of cannibalized techniques, describe them, and note how DART and/or DESI utilizes them.

    Cannibalized Ionization Method

    How does the Ionization Method work?

    Used in DART/DESI? Give evidence.

     Chemical Ionization

    (CI/APPCI)

     

     

     Electrospray

    (ESI)

     

     

    Fast Atom Bombardment

    (FAB)

     

     

    Secondary Ion Mass Spectrometry

    (SIMS)

     

     

     

     

     
    1. How was it characterized? – Each of these two techniques has been described in a leading instrumentation journal, which requires that sufficient evidence be given to describe their performances.

    Quality Characterized

    DART: Value and Experimental Description

    DESI: Value and Experimental Description

    Limit of Detection

     

     

    Response Time

     

     

     MS Spectra Features (single/ multiple charges, soft/hard)

     

     

    Linear Range

     

     

    Spatial Resolution

     

     

     

     

     
    1. How can it be used? – the excitement for these ionization techniques comes from their almost universal use. The number of applications is astounding, but there are some themes that both papers touch upon. The applied applications for these two techniques:

    Application

    DART

    DESI

    Forensics (explosives)

     

     

    Forensics (other)

     

     

    Pharmaceuticals

     

     

    Medical Diagnostics

     

     

    High-throughput

     

     

    Proteins

     

     

    in vivo Analysis

     

     

    Foods

     

     

     

    1. What do you think? – These techniques are ~10 years old now, are they the next big thing in MS? In analytical chemistry? What limitations might they impose?

     

     

     

     

     

    Contributors and Attributions

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