Three Gurus of Comprehensive Chromatography

With the 42nd ISCC and 15th GC×GC Symposia soon rolling into Riva Del Garda, we grill three superlative separation scientists on the progress – and pitfalls – of comprehensive chromatographic techniques.

April 2018

What techniques fall under the umbrella of “comprehensive chromatography”?

Pat Sandra: For me (by definition) comprehensive chromatography requires two-dimensional (chromatographic!) separation with on-line, full continuous development in both dimensions. Off-line fraction collection after the first dimension and analysis on a second column is, in my definition, not comprehensive, and neither are heart-cutting (for example, GC-GC) and multiple heart-cutting (for example, mLC-LC) methods.

All individual chromatographic modes combined on-line in two dimensions can be considered comprehensive. Combining phases is only possible with LC and SFC as they are both in the fluid state.

Lourdes Ramos: For years, the main (and almost exclusive) comprehensive chromatography techniques (CCTs) in use by researchers have been GC×GC and LC×LC, although the latter has been slower to develop. Several research groups have now started to explore the feasibility of alternative couplings, in particular SFC×SFC and CE×CE. Investigations are at an early stage but the promising results reported to date and the potential advantages for particular application fields (for example, SFC×SFC in oil and petrochemical research) will encourage further evaluation of these new CCTs.

Peter Tranchida: Good answers – I will only add that there have also been a few LC×GC experiments reported over the years. However, heart-cutting LC-GC appears to have a much more solid basis, and a wider past, present and (probably) future use. Apart from GC×GC and LC×LC, it is hard to make predictions on the future of other comprehensive 2D chromatography methodologies, as they are currently used in only a few research groups.