GC–MS

Gas chromatography coupled to mass spectrometry (GC-MS) applies the same hyphenated separation-and-detection principle to volatile and thermally stable...

Gas chromatography coupled to mass spectrometry (GC-MS) applies the same hyphenated separation-and-detection principle to volatile and thermally stable compounds amenable to gas-phase chromatographic separation, and is particularly well suited within medicinal chemistry practice to residual solvent analysis (addressed in detail in Phase 4), volatile synthetic intermediate characterisation, and the identification of volatile impurities that would not be amenable to liquid chromatographic analysis. Electron ionisation, the standard GC-MS ionisation technique, produces extensive, highly reproducible fragmentation that, unlike the soft ionisation typically used in LC-MS, generates rich structural information directly from the fragmentation pattern itself and allows unknown compounds to be identified with high confidence by comparison against extensive, well-established reference spectral libraries.