Column switching analysis with packed-capillary columns in gas chromatography.

By introducing sequentially connected two packed-capillary columns, a wide range of volatile compounds were successfully separated in gas chromatography. The hyphenation of two packed-capillary columns of 1.0 mm i.d. was accomplished using a conventional 6-port valve, where the temperature of each column was individually controlled in the respective column ovens. These columns were prepared with two different types of sorbents, each having a different selectivity, in order to separate a wide range of compounds, including permanent gases, volatile alcohols and other typical volatile organic compounds. With a simple valve switching operation, the complex sample mixtures were rapidly separated and detected.