Column Selection and Optimization for Comprehensive Two-Dimensional Gas Chromatography A Review

Compared to one-dimensional gas chromatography, comprehensive two-dimensional gas chromatography (GC x GC) method development is significantly more complex because more method development choices need to be made and because of the complex interplay of the primary and secondary parameters; the individual dimensions cannot be optimized separately. Also, optimization is restricted by requirements such as the modulation criterion and upper temperature limits of the individual columns. In general, the internal diameter of the primary column is larger than the internal diameter of the secondary column which complicates the optimization and leads to sub-optimal flow settings, column loadability issues and indirectly a reduction of the overall separation efficiency. In this review, papers concerning method development for comprehensive two-dimensional gas chromatography (GC x GC) are discussed and general guidelines are proposed with the focus on selecting the GC x GC instrumental set-up and column-set and optimization of the GC x GC settings.