Modulation techniques and applications in comprehensive two-dimensional gas chromatography (GC x GC).

Anal Bioanal Chem

Dow Deutschland GmbH & Co. OHG, Analytical Sciences, 77836 Rheinmünster, Germany.

Published: July 2002

More than a decade after Phillips' first published work this article reviews recent developments in comprehensive two-dimensional gas chromatography (GC x GC). Special attention is devoted to the further development and diversity of modulation devices. These include heated sweepers, cryofocused modulators, and a variety of diaphragm valve-switching strategies. It is demonstrated that all modulation approaches can be very well suited to GC x GC, depending on the particular application. Diaphragm-valve modulation is very powerful for volatile organic compounds. Slotted heater and cryofocused modulation are preferred for samples that contain non-volatile components. Applications ranging from petroleum to environmental and biological samples are illustrated. Extension of the technique to GC x GC-mass spectrometry (MS) is also discussed and trends for future research activity are pointed out.

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http://dx.doi.org/10.1007/s00216-002-1318-7DOI Listing

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