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  2. Gas chromatography–mass spectrometry - Wikipedia

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

    The mass spectrometry process normally requires a very pure sample while gas chromatography using a traditional detector (e.g. Flame ionization detector) cannot differentiate between multiple molecules that happen to take the same amount of time to travel through the column (i.e. have the same retention time), which results in two or more ...

  3. Two-dimensional chromatography - Wikipedia

    en.wikipedia.org/wiki/Two-dimensional_chromatography

    Gas chromatography-mass spectrometry (GC-MS) is a two-dimensional chromatography technique that combines the separation technique of gas chromatography with the identification technique of mass spectrometry. GC-MS is the single most important analytical tool for the analysis of volatile and semi-volatile organic compounds in complex mixtures. [7]

  4. 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 ]

  5. 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.

  6. Mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Mass_spectrometry

    Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a mass spectrum, a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures.

  7. Isotope dilution - Wikipedia

    en.wikipedia.org/wiki/Isotope_dilution

    In a typical gas chromatography analysis, isotopic dilution can decrease the uncertainty of the measurement results from 5% to 1%. It can also be used in mass spectrometry (commonly referred to as isotopic dilution mass spectrometry or IDMS), in which the isotopic ratio can be determined with precision typically better than 0.25%. [5]

  8. Mass chromatogram - Wikipedia

    en.wikipedia.org/wiki/Mass_chromatogram

    A mass chromatogram is a representation of mass spectrometry data as a chromatogram, where the x-axis represents time and the y-axis represents signal intensity. [1] The source data contains mass information; however, it is not graphically represented in a mass chromatogram in favor of visualizing signal intensity versus time.

  9. Sample preparation in mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Sample_preparation_in_mass...

    GC is a method involving the separation of different analytes within a sample of mixed gases. The separated gases can be detected multiple ways, but one of the most powerful detection methods for gas chromatography is mass spectrometry. After the gases separate, they enter the mass spectrometer and are analyzed.