2015 Volume 36 Issue 2 Pages 51-55
A novel column packing material, chondroitin sulfate-modified silica gel (ChS-silica), was developed for use as a stationary phase or capillary electrochromatography. The sulfonic acid groups on the ChS-silica supported electroosmotic flow at low pH and served as a strong cation-exchanger. Analytes are likely retained on ChS-silica by hydrophilic interactions (HI) and strong cation-exchange; this was verified by investigating the effects of mobile phase composition and buffer concentration on the retention of neutral polar and basic compounds. The baseline separation of seven basic pharmaceuticals was achieved using an applied voltage of 10 kV and a mobile phase consisting of 5 mM phosphate buffer (pH 7.0) and 70% acetonitrile. A column efficiency of 153000-410000 N/m for strongly retained compounds was observed.