Principle of Operation
DESI is a combination of electrospray (ESI) and desorption (DI) ionization methods. Ionization takes place by directing an electrically charged mist to the sample surface that is a few millimeters away. The electrospray mist is attracted to the surface by applying a voltage on the sample holder. After ionization, the ions travel through air into the atmospheric pressure interface which is connected to the mass spectrometer. DESI is a technique that allows for ambient ionization of a trace sample at atmospheric pressure, with little sample preparation.
Read more about this topic: Desorption Electrospray Ionization
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