Chapter 7 - Multidimensional and comprehensive gas chromatography

Abstract

The basic principles, instrumentation, and applications of two-dimensional gas chromatography (2D GC) are examined. 2D GC is performed with a pair of standard GC columns coupled with a special interface. Samples are initially injected into the primary column. The interface controls component transfer from the primary column to the secondary column. Components are detected as they exit the secondary column. Three basic forms of 2D GC have been developed. Backflushing 2D GC separates an entire class of analyte components from the sample matrix. A precisely timed change in the primary column flow direction removes matrix components that would otherwise coelute with the analytes. Heartcutting 2D GC isolates a few selected components from a complex mixture by only allowing primary column effluent containing analytes to reach the secondary column. Comprehensive 2D GC (GC×GC) couples a standard GC separation on the primary column with a series of high-speed separations on the secondary column. GC×GC can be used for the isolation of targeted analytes, class separations, and the comprehensive analysis of sample composition.