GC/MS (Gas Chromatography/Mass Spectrometry)
GC/MS (Gas Chromatography/Mass Spectrometry) is one of the most useful and informative analytical techniques used to identify organic molecules.
When a molecule is ionized by bombarding it with electrons or small ionizing molecules, a group of ions (fragments with different masses) is obtained.
Frequently the parent molecule ion is also formed providing the molecular weight of the material. The fragmentation pattern or mass spectrum, which is obtained by plotting the relative abundance of each ion versus the mass-to-charge ratio (m/e) is characteristic of a molecule and can be used for identification purposes.
The GC is used to separate the different components in a mixture prior to analyzing each component (molecule) by the mass spectrometer. A Hewlett-Packard 6890 GC and 5973 mass spectrometer system is used at NDE with the capability for measuring constituents in a sample at the nanogram levels.
Different columns, injectors and interfaces are available to allow for the handling of different types of samples.