Gas chromatography (GC) – mass spectrometry (MS) combines GC and MS to identify different substances and is capable of detecting trace elements thus allowing for the analysis of very small amounts of sample. In GC the compounds are separated between a liquid stationary phase and a gas mobile phase and is suitable for the analysis of compounds that can be vaporized without decomposing. Separation of components from a mixture is primarily based on differences in boiling point (or vapor pressure). Separation is achieved based on the molecules’ difference in retention time where a downstream mass spectrometer then captures, ionizes, accelerates, deflects and detects the ionized molecules separately based on their mass-to-charge ratio.
Agilent 6890N gas chromatograph coupled with Agilent 5973 Network Mass Selective Detector. For specifics visit: https://www.agilent.com/cs/library/specifications/Public/5989-3290EN.pdf and http://www.agilent.com/en-us/support/mass-spectrometry/a03808.