Two-dimensional gas chromatography GC-GC and GCxGC

The analysis of volatile or potentially volatile compounds is nowadays generally carried out by gas chromatography, mainly on capillary columns. Despite advances in this technique, the analysis of certain mixtures can still prove very delicate. These can be highly complex mixtures such as natural extracts, essential oils for example, petroleum products or even certain environmental extracts.

These extracts are often characterized by the presence of a large number of constituents, in varying concentrations. In such samples, co-elutions can be very numerous, complicating identification and quantification. As a result, it can be very difficult to obtain a mass spectrum that is sufficiently sharp to allow component identification. Even the parallel use of different types of column is not always satisfactory.

Two-dimensional chromatography techniques involve separating analytes on two different columns in series. In a single analysis, it is then possible to significantly increase separation power. These techniques fall into two main families: GC-GC and GCxGC.