Semi-rotating cryogenic modulator for comprehensive two-dimensional gas chromatography

A laboratory-made cryogenic modulator for comprehensive two-dimensional gas chromatography (GCx GC) was constructed and evaluated. Analytes were trapped with carbon dioxide and desorbed with heated GC oven air. The GC x GC system included a non-polar first-dimension column and a semi-polar second-dimension column connected to a flame ionisation detector. A laboratory-written Matlab-based program was used for the data analysis. Peak widths at half height for n-alkanes, obtained with use of new modulator, were at narrowest 60 ins.