Liquid Chromatography Mass Spectrometry (LC-MS)
LC-MS at a glance
LC-MS is a versatile and highly sensitive analytical technique for the measurement of small molecular weight compounds in a diverse range of sample types. It uses a series of mass detection systems to provide both quantitative and qualitative analyses. Situated in the Centre for Analytical Bioscience within the School of Pharmacy our MS facilities are ideal for small molecule (<2000m/z) analysis and are complemented by a suite of HPLC or specialised surface analysis interfaces (DESI, LESA) with specialist software for data interpretation.
- Quantification of drug/drug metabolites / endogenous compounds / contaminants in cells, biofluids, tissues and environmental samples.
- Characterising metabolic effects of perturbations to biological system e.g drug-induced changes to intracellular metabolite pathways.
- Metabolic profiling, metabolomics, biomarker discovery, mass spectrometry surface imaging.
How does LC-MS Work?
Liquid chromatography (LC) provides a universal separation of chemical components in solution-based mixtures. It does so by the different affinities of the chemical compounds with a liquid mobile phase flowing through a stationary phase.
Mass spectrometry (MS) involves the ionisation of chemical species, followed by the detection of the mass-to-charge ratio (m/z) and intensity of the various ionised analytes. In the case of LC-MS this is following a chromatographic separation.
The huge complexity of the metabolites in biological systems has lead to LC-MS being utilised to reduce sample complexity by separating out the various sample components prior to their MS detection. Therefore, LC-MS is a powerful analytical technique not only for the quantification of small biomolecules (metabolites) but also for the identification of unknown and known compounds in biological samples.
While traditionally a bulk analysis, modern technical adaptations usually pertaining to the ionisation method, allow LC-MS variants to be used as a powerful complimentary surface analytical tool.
Our LC-MS Facilities
Waters Quattro Ultima LC-MS/MS:
Suitable for targeted analysis of drugs and small molecules (m/z range 100-2000).
Electrospray or APCI ionisation in either positive or negative ionisation modes.ABI 4000 QTRAP Quadrupole Linear Ion Trap LC- MS/MS.
ABI 4000 QTRAP Quadrupole Linear Ion Trap LC-MS/MS:
- Quantitative and qualitative targeted metabolite profiling, and for the identification of unknowns.
- Advanced MS scanning options and information dependent acquisition offer unique approaches to metabolite pro ling and identification.
ThermoFisher Exactive (Orbitrap technology) high resolution accurate mass spectrometer LC-MS:
- Small biomolecule pro ling and identification. Quantitative and qualitative information.
- Metabolomics and lipidomics.
- Highly accurate mass measurements to <5 ppm. Range m/z 80-2000.
- Ultra-high performance liquid chromatography available
Thermo LTQ Velos Ion Trap LC-MSn:
- MS fragmentation analysis and confirmation of chemical identity.
- Ultra-high performance liquid chromatography available.
Prosolia DESI-MS 2D interface for Desorption Electrospray surface analysis (DESI):
- Surface MS analysis/imaging under ambient conditions.
- Advantages where UHV analysis may not be suitable. Alternative to ToF-SIMS and MALDI.
Triversa Nanomate, Liquid Extraction Surface Analysis (LESA):
- Surface extraction/analysis under ambient conditions.
- Advantages where UHV analysis may not be suitable. Alternative mass spectrometric analysis of sample surfaces to ToF-SIMS and MALDI.
Publications of Interest
- M.Montowska, W.Rao, M.R.Alexander, G.A.Tucker, D.A.Barrett. Rapid Detection of Peptide Markers for Authentication Purposes in Raw and Cooked Meat Using Ambient Liquid Extraction Surface Analysis Mass Spectrometry. Spectrometry. Anal. Chem 86 (2014) 10257-10265
- A.Surrati, R.Linforth, I.D.Fisk, V.Sottile, D-H.Kim. Non-destructive characterisation of mesenchymal stem cell differentiation using LC-MS-based metabolite footprinting. Analyst 141 (2016) 3776-3787
- A.Wong, D.R.Sagar, C.A.Ortori, D.A.Kendall, V.Chapman, D.A.Barrett. Simultaneous tissue profiling of eicosanoid and endocannabinoid lipid families in a rat model of osteoarthritis. J. Lipid Res 5 (9) (2014) 1902-1913