Trace metal analysis of natural waters by ICP-MS with on-line preconcentration and ultrasonic nebulization

Abstract

Concentrations of Mn, Ni, Cu, Zn and Pb in natural waters were measured by inductively coupled plasma mass spectrometry (ICP-MS) with on-line preconcentration using Toyopearl TSK-immobilized 8-hydroxyquinoline resin columns and ultrasonic nebulization. Trace metal concentrations, quantified after analyzing calibration standards, were measured in 3 mL samples in under 15 min with better than 5% precision. Method detection limits were 0.26, 0.86, 1.5, 10 and 0.44 ng L –1 for Mn, Ni, Cu, Zn and Pb, respectively. The accuracy of the method was demonstrated by results from runs of certified reference materials SLRS-3 and CASS-3, which have very different ionic strengths. This on-line system was successfully applied to measure water column trace metal concentrations in Galveston Bay, Texas, and the results compared favorably with those obtained using state-of-the-art off-line preconcentration techniques.