Two-Dimensional Capillary GC/FT-IR

Abstract

Two-dimensional glass capillary gas chromatography/ Fourier transform infrared spectroscopy (GC4/FT-IR) is an effective technique for the analysis of very minor sample constituents as well as complex volatile mixtures. The two-dimensional system described here uses multicolumns and, for added separation capability, multiovens with independent temperature control. A fraction or fractions of the sample are transferred from the first column to a second column via a microswitching valve. With this approach, some of the problems routinely encountered with GC/FT-IR with the use of a single chromatographic separation are eliminated. The coupling of high- and low-capacity columns gives an extended working dynamic range for GC/FT-IR. In addition, column switching with repetitive cryofocusing onto the second chromatographic column may be used to enrich trace components prior to spectroscopic analysis.