Christopher McEleney, Christopher Roulston, John Gillespie,Garrett Farrell, William Scott and Denis McCrudden*
This study describes the development of a robust method for the electro analytical quantification of trace copper(II) in non-deaerated organic samples of macro algae by square wave anodic stripping voltammetry (SWASV). The indicator electrode employed was an antimony thin film coated onto a glassy carbon electrode (SbFE) support. The modified electrode was successfully applied for the sensitive and selective detection of trace copper in real sea weed samples following acid digestion. Copper(II) calibrations in the range of 2-10 μgL-1 (LOD=0.53 μgL- 1) in model solutions of 0.01 M hydrochloric acid (pH 2) containing 1 mgl-1 of antimony(III) were made possible by the addition of 30 μgL-1 cadmium(II). The method proved to be robust by the quantification of copper(II) in a 25 ml cell, containing 5 ml of sample digest. Dried seaweed samples, Palmaria palmata, Laminar digitata and Fucus vesiculosus in the resulting cell were found to contain 3.06, 2.02 and 0.857 μgL-1 respectively (RSD=2.9%). Furthermore, 0.857 ± 0.1 μgL- 1 copper(II) was determined in the Fucus vesiculosus sample with interferents, zinc(II), cadmium(II), lead(II) and arsenic(II), added at concentrations 15 times greater than the inherent concentration of copper(II).