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  2. Gas chromatography - Wikipedia

    en.wikipedia.org/wiki/Gas_chromatography

    Gas chromatography (GC) is a common type of chromatography used in analytical chemistry for separating and analyzing compounds that can be vaporized without decomposition. Typical uses of GC include testing the purity of a particular substance, or separating the different components of a mixture. [ 1 ]

  3. Elution - Wikipedia

    en.wikipedia.org/wiki/Elution

    Elution principle of column chromatography. In analytical and organic chemistry, elution is the process of extracting one material from another by washing with a solvent: washing of loaded ion-exchange resins to remove captured ions, or eluting proteins or other biopolymers from a gel electrophoresis or chromatography column.

  4. List of purification methods in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_purification...

    Chromatography employs continuous adsorption and desorption on a packed bed of a solid to purify multiple components of a single feed stream. In a laboratory setting, mixture of dissolved materials are typically fed using a solvent into a column packed with an appropriate adsorbent, and due to different affinities for solvent (moving phase ...

  5. Chemical ionization - Wikipedia

    en.wikipedia.org/wiki/Chemical_ionization

    Chemical ionization for gas phase analysis is either positive or negative. [12] Almost all neutral analytes can form positive ions through the reactions described above. In order to see a response by negative chemical ionization (NCI, also NICI), the analyte must be capable of producing a negative ion (stabilize a negative charge) for example ...

  6. Chromatography - Wikipedia

    en.wikipedia.org/wiki/Chromatography

    Pyrolysis–gas chromatography–mass spectrometry is a method of chemical analysis in which the sample is heated to decomposition to produce smaller molecules that are separated by gas chromatography and detected using mass spectrometry. Pyrolysis is the thermal decomposition of materials in an inert atmosphere or a vacuum.

  7. List of chemical analysis methods - Wikipedia

    en.wikipedia.org/wiki/List_of_chemical_analysis...

    Flow injection analysis (FIA) Fourier transform infrared spectroscopy (FTIR) G. Gas chromatography (GC) Gas chromatography-mass spectrometry (GC-MS)

  8. Gas chromatography–mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Gas_chromatography–mass...

    For the analysis of volatile compounds, a purge and trap (P&T) concentrator system may be used to introduce samples. The target analytes are extracted by mixing the sample with water and purge with inert gas (e.g. Nitrogen gas) into an airtight chamber, this is known as purging or sparging.

  9. Internal standard - Wikipedia

    en.wikipedia.org/wiki/Internal_standard

    In gas chromatography-mass spectrometry (GC-MS), deuterated compounds with similar structures to the analyte commonly act as effective internal standards. [8] However, there are non-deuterated internal standards such as norleucine, which is popular in the analysis of amino acids because it can be separated from accompanying peaks. [9] [10] [11]