Comprehensive two-dimensional gas chromatography: metrics, potentials, limits

Metrics for evaluation of separation performance of comprehensive two-dimensional gas chromatography (GC×GC) and for quantitative comparison of that performance with similar performance of its 1D (one-dimensional) counterparts are described. The performance improvement can be expressed via reduction in the saturation of a chromatogram or—in the case of the uniform distribution of peaks along the second dimension—via the peak capacity gain due to GC×GC. An order of magnitude peak capacity gain due to the comprehensive GC×GC is possible under optimal conditions. Optimal parameters of the second dimension column as well as the optimal operational conditions for that column and for the modulator in a comprehensive GC×GC are also presented.