Mass Spectrometry is an analytical technique used to determine the mass of molecules and gain information on molecular structure. It is an excellent method for identifying small molecular species, and because the compounds fragment during their path to the detector, the observation of these ‘building blocks’ help us to discover how the atoms are connected, rather like a jigsaw puzzle. Pure compounds may be analysed, but also mixtures.

MS in Perkin Building

Our principal instrument is equipped with a HPLC front-end allowing for chromatographic separation of complex mixtures, before entering the MS, picking out the components is therefore more straightforward. Alternatively, we may sample directly, without prior separation.

MS in Lyell Centre

Accelerated Solvent Extraction (2´ASE) 350 System 

The ASE 350 is a modified temperature-pressure extraction system that allows for rapid, high-efficiency “removal” of lipids from diverse materials, including geologic matrices (e.g., sediment), inorganic substrates (e.g., ceramic artefacts), and biological tissues (e.g., plant leaves or animal bone). The ASE 350 at the Lyell Centre can also allows for gradient elution with up to 3 solvents vis-à-vis conventional liquid chromatographic methods.  With few exceptions, the extraction process also does not degrade or alter non-organic components (e.g., pedogenic carbonates) of the materials extracted. 

Gas Chromatograph-Flame Ionization Detector
(GC-FID; “Lucy”) 

  • ThermoScientific TRACE 1310 GC with Programmed Temperature Vaporizing (PTV) injector and AI 1310 155-position autosampler 
  • N.B., This instrument is configured to handle solvated (dissolved/liquid) samples only! 

The GC-FID is a workhorse instrument that allows us to quantify the concentrations of diverse organic molecules, whether standards or extracted from a sample.  The GC-FID at the Lyell Centre accommodates dual columns, which are interchangeable; installed for now are a 60-m TG-5SilMS (e.g., phenol, PAH, hydrocarbon separations) and a 60-m TG-17SilMS (e.g., pesticides, sterol separations).  The detection limit is about 10 pg (organic carbon) per microliter, and the average uncertainty (propagated) for molecular concentrations is <2% (relative standard deviation).  The GC-FID at the Lyell Centre is also equipped with an autosampler, which facilitates increased throughput.  

Gas Chromatograph-Mass Spectrometer (GC-MS; “Stanley One”) 

  • ThermoScientific TRACE 1300 GC with dual Programmed Temperature Vaporizing (PTV) and Split/Splitless (SSL) injectors and TriPlus RSH liquid/headspace autosampler coupled to a ISQ LT (single quadropole) MS  
  • N.B., This instrument is configured to handle solvated (dissolved/liquid) samples and headspace (i.e., volatiles) alike. 

GC-MS techniques are useful for compound identification, and this instrument allows us to fragment the molecules in a sample into characteristic daughter ions, which then are useful for compound identification.  This approach is especially good for samples with unknown or complex organic molecular composition, especially when run in selected ion mode.  Our current GC-MS setup features a detection limit of 100 pg on-column with a relative standard deviation in response of <5%. At present, this instrument is equipped with a 60-m TG-5SilMS (c.f., description above) column. 

Gas Chromatography isotope ratio monitoring Mass Spectrometer (GC-irmMS; “Miracle”) with peripheral GasBench 

  • ThermoScientific TRACE 1310 GC with Split/Splitless (SSL) injector and TriPlus RSH liquid autosampler and PAL GasBench both coupled to a Delta V Plus MS via a continuous flow interface 
  • N.B., This instrument is configured to handle solvated (dissolved/liquid) samples only! 

The GC-irmMS is, in essence, a modified GC-MS that further allows us to measure the stable isotopic composition (2H, 13C, 15N, 18O, 34S) of discrete organic molecules – so-called compound-specific isotope analysis (CSIA).  Because it detects individual isotopomers, this instrument demands comparatively large molecular concentrations of >10 ng for each molecule of interest.  The GasBench feature allows us to measure stable isotope signatures of headspace gases either directly or after acid digestion (e.g., carbonates).  Both configurations achieve an average reference precision (1s) of between about 0.1‰ (13C) and 1‰ (2H) for signals of >50 nA. 

Now, watch this!