DETERMINATION OF TRACE METALS BY lON-CHROMATOGRAPHY WITH CHEMILUMINESCENCE DETECTION

Abstract

It is generally considered that the detection step for the determination of trace metals by liquid-chromatographic systems is the weakest area of the analytical procedure. Various post-column reagent systems, for trace metal analysis, based on the highly sensitive luminol-peroxide chemiluminescence (CL) reaction have been developed and are described. A simple cation-exchange chromatographic system was developed and used to separate cobalt from other metal ions. These cobalt ions were detected using an optimised luminol-peroxide CL post-column reagent. A detection limit of 0.5 ng 1̵¹ was achieved without the need for preconcentration, for a 200 µl sample. The cobalt content of a rice flour certified reference material was determined using this system and gave good agreement with the certificate value.