Ion chromatography determination of trace silver ions using hydrophilic resins with chemiluminescence detection

Abstract

This paper details the development of an ion chromatographic method for the determination of silver using cation-exchange resins. The work clearly shows the major improvement in chromatographic performance when using hydrophilic substrates as against hydrophobic-based ones, giving good peak shapes with little tailing.

A novel post-column reaction detection system is also presented, based on the oxidation of luminol with peroxodisulfate. Good quantitative performance was found between 1 and 100 µg l^–1 with only slight curvature of calibration graphs at the high concentration end. Sensitivity was very good, producing a detection limit of 0.5 µg l^–1. The presence of iodide caused a major interference, but this could be eliminated by pre-treatment of the reagent solutions with peroxodisulfate.