Determination of Carbohydrates by Anion Exchange Chromatography with Pulsed Amperometric Detection

Abstract

Carbohydrates such as sugar alcohols, monosaccharides, disaccharides, and other oligosaccharides are separated as anions by ion exchange chromatography with a sodium hydroxide eluent. Retention time and selectivity are controlled by varying eluent strength and column temperature. The carbohydrates are detected by oxidation at a gold electrode. A repeating sequence of three potentials electrochemically cleans the electrode surface of oxidation products and other interfering species. Detection limits are as low as 30 ppb for sugar alcohols and monosaccharides, and about 100 ppb for oligosaccharides. Other species containing CHOH groups can also be detected, such as alcohols and glycols.