MDGC, multidimensional gas chromatography

Principles and Characteristics Multidimensional gas chromatography (MDGC) is widely used, due to the mobile-phase compatibility between the primary and secondary separating systems, which allows relatively simple coupling with less-complicated interfaces. In its simplest form, 2DGC can be carried out in the off-line mode. The most elementary procedure involves manual collection of effluent from a column, followed by reinjection into another column of a different selectivity (e.g. from an apolar to a polar column). Selecting proper GC-column combinations is critical. In on-line mode, the interface in MDGC must provide for the quantitative transfer of the effluent from one column... 

Mosandl A, Schubert V, Stereoisomeric flavor compounds XXXVII Enantiomer separation of l-alken-3-yl esters and their chirality evaluation from essential oils using multidimensional gas chromatography (MDGC),/ Essen Oil Res 2 121— 132, 1990. 

A Enantioselective multidimensional gas chromatography (MDGC)-mass spectrometry (MS), B gas chromatography (GC)-isotope ratio mass spectrometry (IRMS) multielement analysis (5 C, values), C enantiomeric purity (%), D total percentage (%)... 

Multidimensional Gas Chromatography (MDGC) Basic Protocol 2 Sensory Discrimination of Chiral Flavor Compounds Using Gl.4.4... 

DETERMINATION OF ENANTIOMER COMPOSITION USING MULTIDIMENSIONAL GAS CHROMATOGRAPHY (MDGC)... 

Figure 9. Proposal for a linked HRGC-FTIR-MS system with integrated multidimensional gas chromatography (MDGC) to be used with full sensitivity of both spectroscopic techniques. A Packed GC-FTIR-MS. B Traditional MDGC system with FTIR-MS. C Proposed "DYCOM" system consisting of packed-capillary MDGC-HRGC-FTIR-MS. a Loading capacity of column. b,c Detection limits of FTIR and MS, respectively. Further explanations, cf. text.

The aim of the present study was the isolation and identification of new flavor compounds from Scheurebe wine at trace level. For enrichment purposes preparative multidimensional gas chromatography (MDGC) was used. The structure elucidation of the isolated compounds was on the basis of spectroscopic methods (NMR, GC-FTIR, GC-MS) and synthesis as well. The sensory properties of the isolated compounds were correlated with the typical aroma profile of Scheurebe wines. 

Analysis of trace compounds. All fractions were checked by capillary gas chromatography (GC) with FID and sulfiir specific detection (flame photometric detector, FPD ThermoQuest CE, Egelsbach). Subsequently the different fractions were analyzed by capillary gas chromatography-mass spectrometry (GC-MS). Specific unknowns were enriched by preparative multidimensional gas chromatography (MDGC). For further structure elucidation complementary analyses using GC-MS and capillary gas chromatography-Fourier transform infrared spectroscopy (GC-FTIR) as well as H-NMR were applied. All new compounds have been synthesized and characterized by GC-olfactometry (GC-0). 

The application of multidimensional gas chromatography (MDGC) to essential oil analysis is a great development in the determination of such complex samples. This is an appropriate approach when there are zones on the chromatogram where the peaks are not well resolved, which is a common situation in natural samples. The fractions corresponding to the zones with unresolved peaks are transferred to a second column containing a different stationary phase, where they are separated and completely resolved. Therefore MDGC permits the separation of poorly resolved peaks and increases resolution, with the final result of an improvement in both identification and quantification of components of essential oils. 

Multidimensional gas chromatography (MDGC) is known to allow quantitative determinations of fractions that have been heart-cut from the first column and further separated in... 

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