Analytical Sciences

Abstract − Analytical Sciences, 25(11), 1369 (2009).

Capillary Chromatography Based on the Tube Radial Distribution of Aqueous-Organic Mixture Carrier Solvents: Effects of the Inner-Wall Characteristics of the Fused-Silica Tube on Separation Performance
Department of Chemical Engineering and Materials Science, Faculty of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321, Japan
A capillary chromatography system was developed using an open capillary tube and a water-acetonitrile (hydrophilic)-ethyl acetate (hydrophobic) mixture carrier solution. In this study, we examined the effects of the inner-wall characteristics of a fused-silica capillary tube on the separation performance in this system. Untreated (silanol group-intact) and inactivated (silanol group-end-blocked) fused-silica capillary tubes were used. The mixture analyte of 1-naphthol and 2,6-naphthalenedisulfonic acid was injected into two types of capillary tubes. They were eluted from both tubes in this order with water-acetonitrile-ethyl acetate (volume ratio 2:7:4) mixture carrier solution, and eluted in reverse order with water-acetonitrile-ethyl acetate (volume ratio 15:3:2). The peak shapes observed here were analyzed while considering the inner-wall characteristics of the capillary tubes from the viewpoint of the tube radial distribution of the carrier solvents in the tubes.