Multi-dimensional spectrometry

A two-dimensional picture like that in Fig. 5.1 represents the most common analytical presentation of results however, multi-dimensional pictures can occur, as in mass spectrometry, when measurements are made for the same analyte but with varying ionization energy and/or magnetic field strength. 

Huber, J.F.K., Kenndler, E., Reich, G. (1979). Quantification of the information content of multi-dimensional gas chromatography and low resolution mass spectrometry in the identification of doping drugs. J. Chromatogr. 172, 15-30. 

Vitali, B., Wasinger, V., Brigidi, P., Guilhaus, M. (2005). A proteomic view of Bifidobacterium infantis generated by multi-dimensional chromatography coupled with tandem mass spectrometry. Proteomics 5, 1859-1867. 

Maynard, D.M., Masuda, J., Yang, X., Kowalak, J.A., Markey, S.P. (2004). Characterizing complex peptide mixtures using a multi-dimensional liquid chromatography-mass spectrometry system Saccharomyces cerevisiae as a model system. J. Chromatogr. B Analyt. Technol. Biomed. Life Sci. 810, 69-76. 

Gergely, V. et al. Selenium speciation in Agaricus bisporus and Lentinula edodes mushroom proteins using multi-dimensional chromatography coupled to inductively coupled plasma mass spectrometry. J. Chromatogr. A. 2006, 1101,94-102. 

Multi-dimensional Protein Identification Technology (MudPIT) incorporates several liquid chromatography steps with tandem mass spectrometry to identify proteins in... 

Fig. 6.14 Schematic diagram of a multi-dimensional gas chromatographic-pyrolysis-isotope ratio mass spectrometry (MDGC-P-IRMS) device. After [210] with kind permission of the American Chemical Society. For application see Fig. 6.20...

Instead by solvent extraction [207], aroma compounds from aqueous media, e.g. fruit juices, can even be separated and enriched by techniques of solid phase micro extraction (SPME), preferably from the headspace [208] , corresponding devices can often be directly connected to GC systems. These techniques provide the complete spec-tmm of the individual compounds of an aroma. As it will normally not be possible and even not necessary to analyse all components of the complex mixture, the separation of its main compounds may demand a multi-dimensional (MD) gas chromatographic system [209[ as displayed in Fig. 6.14 [210[. Examples for the multi-ele-ment/multi-compound isotope analysis by such systems will be given later (6.2.2.4.4, [211[) they can even integrate the identification of the compounds by molecular mass spectrometry and a simultaneous determination of the enantiomer ratios of isomers [210, 211 [. The importance of enantiomer analysis as a tool for authenticity assessment is extensively treated in chapter 6.2.3. 

The ideal detector is universal yet selective, sensitive and structurally informative. Mass spectrometry (MS) currently provides the closest approach to this ideal. The combination of multi-dimensional gas chromatography with high resolution MS or mass-selective detectors in the single ion monitoring (SIM)-mode is currently the most potent analytical tool in enantioselective analysis of chiral compounds in complex mixtures [29]. Nevertheless, it must be pointed out that the application of structure specific detection systems like MS [51] or Fourier transform infrared (FT-IR) [52] cannot save the fundamental challenges to optimum (chiral) resolutions and effective sample clean-up [53]. 

LYT Li, JN Kyranos. Automated multi-dimensional HPLC/UV/MS forquanti-tative method development. Proceedings of the 44th ASMS Conference on Mass Spectrometry and Allied Topics, Portland, OR, 1996, p. 1041. 

Han, X. 2010. Multi-dimensional mass spectrometry-based shotgun lipidomics and the altered lipids at the mild cognitive impairment stage of Alzheimer s disease. Biochim. Biophys. Acta 1801 774-83. 

Andersson, P. E., Demirbuker, M. and Blomberg, L. G. (1993) Characterization of fuels by multi-dimensional supercritical fluid chromatography and supercritical fluid chromatography-mass spectrometry. J. Chromatogr., 641, 347-55. 

X. Han and R. W. Gross, New Developments in Multi-Dimensional Mass Spectrometry Based Shotgun Lipidomics , in Metabolomics, Metabonomics and Metabolite Profiling, ed. W. J. Griffiths, Royal Society of Chemistry, Cambridge, UK, 2008, p. 134. 

Yang, K., Cheng, H., Gross, R.W. and Han, X. (2009) Automated Upid identification and quantification by multi-dimensional mass spectrometry-based shotgun Upidomics. Anal. Chem. 81,4356-4368. 

Han, X., Yang, K. and Gross, R.W. (2012) Multi-dimensional mass spectrometry-based shotgun hpidomics and novel strategies for hpidomic analyses. Mass Spectrom. Rev. 31, 134-178. 

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