Main Page | See live article | Alphabetical index GCMS is an abbreviation for Gas chromatography-Mass spectrometry, an advanced piece of analytical equipment typically used to characterise complex organic mixtures. The Gas chromatography stage will separate the mixture into its constituent parts (i.e. substrate and series of active compounds). Each of these stages will then be passed to the mass spectrometer for individual characterisation. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.