Trace Copper Detection in High Salt Matrices by Laser Enhanced Ionization Spectrometry

Abstract

The detection of trace levels of copper in high salt matrices, including matrices with low ionization potential elements such as alkali and alkaline earth elements and metal sulfate solutions, present unique challenges to conventional methods of analysis like inductively coupled plasma (ICP) atomic emission spectrometry and atomic absorption (AA) spectrometry. In each case the conventional method of analysis possesses sufficient sensitivity to perform the analysis at the 1 ng/mL level in aqueous solutions (1). However in matrices such as seawater and metal sulfate solutions chemical and spectroscopic interferences prevent these methods from achieving this level of sensitivity. This paper describes the use of laser enhanced ionization (LEI) spectrometry to detect copper in 0.5 M sulfate solutions and synthetic seawater at the 0.5 ng/mL level.