Temperature Effect on Separation Performance in Capillary Chromatography based on Tube Radial Distribution of Aqueous-Organic Mixture Carrier Solvents

摘要

We have developed a capillary chromatography system using an open capillary tube made of fused-silica, polyethylene, or poly(tetrafluoroethylene), and a water-hydrophilic/hydrophobic organic mixture carrier solution. This so-called tube radial distribution chromatography (TRDC) system works under laminar flow conditions. Previously, the effects of capillary temperature on separation performance in the TRDC system were examined using a fused-silica capillary tube and a water-acetonitrile-ethyl acetate mixture carrier solution; 1-naphthol and 2,6-naphthalenedisulfonic acid in a model mixture were eluted with baseline separation over the temperature range of 5 - 23°C with the organic solvent-rich carrier solution. In this study, based on the assumption that the phase distribution of inner and outer phases in the capillary tube induced by the tube radial distribution of the carrier solvents did not change with temperature over a limited range, we attempted to apply the van't Hoff equation to the chromatographic data obtained at various capillary temperatures.