Hyphenated Techniques

Comprehensive two-dimensional gas chromatography (GCxGC) was developed in 1991 by Phillips, and as in other hyphenated instruments GCxGC consists of two columns connected serially such that all sample portions emerging from the first instrumental method enter the second and are analysed sequentially. The hyphenation produces two-dimensional data in which each instrument supplies an axis. The only instrumental difference between the designs of GCxGC and GC-MS is the use of another column rather than a mass analyser in the second dimension. In both cases, sample portions eluting from a GC column are fed into a second separation device. GC-MS uses a mass analyser as the second separation device to produce a series of mass spectra from the eluted sample portions. GCxGC uses another GC column as the second separation device to produce a series of chromatograms from the sample portions eluted from the first column.

High-end GCxGC systems use the two-dimensional separation steps (the 1^st dimension is a non-polar GC column, a short, fast, polar GC column is used in the 2^nd dimension) in combination with a TOF(MS) as a third dimension. These systems are used for the analysis of very complex samples such as oils and environmental and food samples. GCxGC-TOF(MS) is also an important analytical tool in the new field of metabolomics.

GCxGC-TOF(MS) Analysis of PAHs in olive oil		Mass traces of the same analysis