Column selection approach to achieve a high peak capacity in comprehensive three-dimensional gas chromatography

Abstract The separation power of comprehensive three-dimensional gas chromatography (GC 3 ) is substantially enhanced through proper selection of the phase volume ratio, β , of each column relative to each other on successive dimensions. Consideration and application of the ratio of phase volume ratios, β r , or β ratio, between successive dimensions has been a relatively un-studied approach to maximize separating power in comprehensive multidimensional GC instrument design. Herein, proper selection of β r in multidimensional GC is shown to control the elution temperature, T e , of analytes throughout a 40 min primary ( 1 D) column separation, and thus better control width-at-base, W , on all three dimensions. Specifically, between the 1 D and secondary ( 2 D) columns, a β r of 0.45 was applied, and between the 2 D and tertiary ( 3 D) columns a β r of 1.0 was applied. A total ideal peak capacity of 30,600, or a peak capacity production of ~770 peaks/min, was accomplished with the GC 3 instrument with the reconfigured parameters. Additionally, due to the complex nature of this three-dimensional data, a novel approach to “slicing” the chromatographic run into user-defined time intervals is shown. This novel way to view the data still elicits a traditional GC×GC chromatograms, but with the focus on 2 D ×  3 D separations. Moreover, due to proper β r selection, every 2 s window (i.e. every 1 D modulation period) is shown to have a peak capacity of ~50–100 for each 2 D ×  3 D separation. This high overall peak capacity (30,600) and peak capacity per 1 D modulation (~50–100), courtesy of proper column selection, is demonstrated to hold great promise to physically separate truly complex mixtures.