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  2. Mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Mass_spectrometry

    Mass spectrometry data analysis is specific to the type of experiment producing the data. General subdivisions of data are fundamental to understanding any data. Many mass spectrometers work in either negative ion mode or positive ion mode. It is very important to know whether the observed ions are negatively or positively charged.

  3. Direct analysis in real time - Wikipedia

    en.wikipedia.org/wiki/Direct_analysis_in_real_time

    In mass spectrometry, direct analysis in real time (DART) is an ion source that produces electronically or vibronically excited-state species from gases such as helium, argon, or nitrogen that ionize atmospheric molecules or dopant molecules. The ions generated from atmospheric or dopant molecules undergo ion-molecule reactions with the sample ...

  4. Electrospray ionization - Wikipedia

    en.wikipedia.org/wiki/Electrospray_ionization

    Electrospray ionization (ESI) is a technique used in mass spectrometry to produce ions using an electrospray in which a high voltage is applied to a liquid to create an aerosol. It is especially useful in producing ions from macromolecules because it overcomes the propensity of these molecules to fragment when ionized.

  5. Matrix-assisted laser desorption/ionization - Wikipedia

    en.wikipedia.org/wiki/Matrix-assisted_laser_de...

    MALDI TOF mass spectrometer. In mass spectrometry, matrix-assisted laser desorption/ionization (MALDI) is an ionization technique that uses a laser energy-absorbing matrix to create ions from large molecules with minimal fragmentation. [1]

  6. Chemical ionization - Wikipedia

    en.wikipedia.org/wiki/Chemical_ionization

    A schematic diagram of chemical ionization source. Chemical ionization (CI) is a soft ionization technique used in mass spectrometry. [1] [2] This was first introduced by Burnaby Munson and Frank H. Field in 1966. [3]

  7. Ion-mobility spectrometry–mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Ion-mobility_spectrometry...

    Ion mobility spectrometrymass spectrometry (IMS-MS) is an analytical chemistry method that separates gas phase ions based on their interaction with a collision gas and their masses. In the first step, the ions are separated according to their mobility through a buffer gas on a millisecond timescale using an ion mobility spectrometer .

  8. Ion source - Wikipedia

    en.wikipedia.org/wiki/Ion_source

    Plasma desorption ionization mass spectrometry (PDMS), also called fission fragment ionization, is a mass spectrometry technique in which ionization of material in a solid sample is accomplished by bombarding it with ionic or neutral atoms formed as a result of the nuclear fission of a suitable nuclide, typically the californium isotope 252 Cf ...

  9. Electron ionization - Wikipedia

    en.wikipedia.org/wiki/Electron_ionization

    This investigation used a new rapid and sensitive electron ionization-gas chromatography–mass spectrometry method in selective ion monitoring mode (SIM) with a single injection of the sample. All the pyrethroid residues were separated by using a GC-MS operated in electron ionization mode and quantified in selective ion monitoring mode.