GCxGC chromatography

FANES Furnace atomic nonthermal emission GCxGC Comprehensive gas chromatography... 

With recent instrumental development, such as fast LC, fast GC and two-dimensional gas chromatography (GCxGC) and advanced tandem hybrid MS detection systems (i.e., QqTOF, QqLIT, Orbitrap) the analysis of complex mixtures... 

In order to manipulate the selectivity of the FT synthesis, there needs to be an understanding of the parameters that control the selectivity. Within Sasol there are many activities to ensure more accurate measurements, e.g., developments in the two-dimensional gas chromatography (GCxGC) technique. This discussion will give a flavor of what Sasol is doing regarding the understanding of Fe-LTFT selectivity. 

Another approach in GC is that of using more power in the separation by doing GCxGC. In this approach, a second column is used with a different type of stationary phase than the primary stationary phase, and fast chromatography using TOF-MS as the detector is carried out [39]. This technique uses only TOF-MS as the detector since it has the most sensitivity for fast-eluting peaks. The method has been applied to complicated matrix analysis. 

The modulator is the heart of the GCxGC system, and is positioned at the confluence of the coupled chromatography columns. The role of the modulator is to trap or isolate compounds present in a given time fraction eluting from the first-dimension column and reinject these components rapidly into the second column. This essentially yields a time-sampled chromatogram, from the first dimension ( D) to the second dimension ( D). It is critical that the modulator is capable of representatively and faithfully sampling peaks eluting from onto D. This can be achieved by either complete or partial transfer of the first-column eluent, however, both techniques are considered comprehensive. 

Fig. 15.5 Illustration of how two overlapping peaks S and ip emerging from the first colmnn (a) are resolved in GCxGC after passage to the second column (b) [31]. Reprinted from Marriott, R, Shellie, R., Principles and applications of comprehensive two-dimensional gas chromatography. Trends Anal. Chem. (2002), 21 573-583 with permission from Elsevier...

Eyres, G., Dufour, J.P> Hallifax, G., Sotheeswaran, S., Marriott, P.J. (2005) Identification of character-impact odorants in Coriander and wild coriander leaves using gas chromatography-olfactometry (GCO) and comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GCxGC-TOFMS). J. Sep. Sci. 28 1061-1074. 

Adahchour, M., Beens, J., Vreuls, R.J.J., Brinkman, U.A.T. (2006) Recent developments in comprehensive two-dimensional gas chromatography (GCxGC). Trends Anal. Chem. 25 438-454, 540-553. 

Reichenbach, S., Ni, M., Kottapalli, V., Visvanathan, A., Ledford, E., Oostdijk, J., Trap, H. (2003). Chemical Warfare Agent (CWA) Detection with Comprehensive Two-Dimensional Gas Chromatography (GCxGC). Chemical and Biological Sensing IV, Proc. SPIE 5085 28-36. 

KEYAVORDS Gas chromatography, atomic emission detection, hetero-atom speciation, sulfur, comprehensive two-dimensional gas chromatography, comprehensive two-dimensional gas chromatography/AED, GCxGC/AED, GCxGC, fuels, gasolines, jet fiels... 

Furthermore, in some cases, these detectors may be used in conjunction with a higher chromatographic resolution/selectivity to minimize matrix interference. Comprehensive two-dimensional gas chromatography (GCxGC) has been under development for more than ten years [10(and references contained therein)] as an enhanced resolution technique. The technique involves continuously transferring or modulating short time periods from a primary column, the first dimension, to a second column of different polarity or selectivity, which serves as the second dimension. The modulation period is typically less than the peak widths observed on the... 

The most characteristic s)mibol of comprehensive two-dimensional gas chromatography (and of any other "comprehensive" coupling) is the multiplex (x), used to abbreviate its full name to GCxGC. Most of the nomenclature and symbols used in GCxGC which are now widely accepted were included by Schoenmakers et al. in a 2003 publication [6]. Their suggestions are used throughout this book. 

An introduction to informatics for comprehensive two-dimensional gas chromatography (GCxGC) should begin with the strikingly beautiful and... 

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