Anion exchange for the determination of arsenic and selenium by inductively coupled plasma mass spectrometry

Abstract

A previously described anion-exchange separation method for the elimination of some of the spectral interferences in inductively coupled plasma mass spectrometry was optimized for the determination of As and Se. Basically, samples are applied to a Dowex-1 × 8 resin column in nitrate form and Cl^– is retained while As and Se are eluted with dilute nitric acid and collected in the eluate. The ArCl⁺ interference on ⁷⁵As⁺ and ⁷⁷Se⁺ was eliminated by more than 99.9% and As and Se were determined in sea-water and human urine. A Dowex-1X8 resin column in acetate form however was observed to be preferable for the determination of As and Se in human serum.