Ion Chromatography of Alkali Metal Ions Using Micellar Bile Salt Coated Stationary Phase

Abstract

A micellar bile salt-coated stationary phase was used for separating alkali metal ions; copper(II) was employed as a lightabsorbing mobile phase for indirect UV detection at 200nm. Lithium, sodium, potassium, rubidium and cesium ions could be separated by the present system, though ammonium ions could not be separated from potassium ions. The detection limits of the analyte ions at a signal-to-noise ratio of 2 were 0.88pmol, or 44μM per injection (0.02μl). The present system was applied to the determination of potassium and sodium ions in beverages.