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A narrow-bore packed column (packed-capillary column) that designed for a direct installation in conventional capillary gas chromatographic (GC) system had been developed. In this column, particulate sorbents that employed in typical GC packed columns were packed into a stainless-steel capillary of 1.0 mm i.d. By attaching a pair of stainless-steel capillaries of 1.27 mm o.d. at both ends of the column, the packed-capillary column can be directly installed into the conventional capillary GC system. In this article, fundamental of the packed-capillary column developed by our research group is mainly reviewed, along with the various applications, such as column switching analysis and evaluation of catalytic property based on the determinations of CO and CO2.

Retention behavior of diazines, consisted of pyrazines, pyridazines and pyrimidines, was studied at various column temperatures in reversed− phase liquid chromatography (RPLC). An increased retention of pyrazines was observed on several types of stationary phases including octadecylsilica (ODS) phases when column temperature was elevated, suggesting an abnormal temperature effect. Similar abnormal temperature effect on the retention was also observed for pyridazines and pyrimidines with an acetonitrile/water mobile phase at elevated column temperatures. On the other hand, no similar trend was found for these analytes with a methanol/water mobile phase. In addition, the retention for pyrazole, imidazole and their methyl derivatives was decreased with increasin gt he column temperature regardless the type of organic modifier in the mobile phase. The results suggest that the abnormal temperature effect on the retention of diazines could be mainly induced by an unusual thermodynamic behavior between the stationary phase and the mobile phase containing acetonitrile.

Surface derivatization of poly(p-phenylene terephthalamide) (PPTA) fibers was studied to prepare novel stationary phases in liquid chromatography (LC). As one type of surface derivatization of synthetic fibers, alkyl or perfluoroalkyl chains as functional groups were introduced to the surfaces of PPTA fibers. When each functionalized fiber-packed column was used for LC, increases in retention power with respect to a variety of compounds were ascertained in comparison with that prepared by an untreated-fiber as the stationary phase. Furthermore, it was indicated that the perfluoroalkyl group introduced fibrous stationary phase showed a specific retention behavior with respect to halogenated benzenes. These results demonstrated that the derivatization of the surfaces of PPTA fibers was successfully carried out. Selectivity differences between the modified-fiber packed columns were also confirmed through the use of some sample probes.