New valve switching modulator for comprehensive two-dimensional gas chromatography

This paper describes a new design for a valve switching modulation system developed for comprehensive two-dimensional gas chromatography (GC x GC). This system is based on the differential flow and is different from the earlier reported in the literature. It has several advantages and constructed of inexpensive, commercially available parts that are easily installed on most gas chromatographs. Operation is easy and robust and requires no external coolants. This new design allows GC x GC analysis to be conducted in any laboratory environment capable of supporting conventional GC and imposes no additional consumable costs. The system is flexible and permits the use of a wide range of stationary phase combinations. The system has been successfully tested for complete material transfer and is suitable for quantitative analysis. The flexibility of this system is demonstrated using several test mixtures that show its extended application in petroleum, biochemistry, and environmental studies. (C) 2008 Elsevier B.V. All rights reserved.