Gas Chromatography - Mass Spectrometry (GC-MS)

Gas Chromatography - Mass Spectrometry (GC-MS)
Block diagram of a gas chromatogram-mass spectrometer. The gas chromatograph column separates the mixture into its components. The quadrupole mass spectrometer scans mass spectra of the components as they leave the column.

As the sample passes through the column the most volatile components move through the column faster than the more volatile components. The separated components leave the column at different times, passing through a tranfer line into the ion source of the mass spectrometer, where the molecules are ionized and allowed to fragment.