title: Voltammetric behaviour and trace determination of copper at a mercury-free screen-printed carbon electrode.
abstract: Screen-printed carbon electrodes (SPCEs), without chemical modification, have been investigated as disposable sensors for the measurement of trace levels of Cu(2+). Cyclic voltammetry was employed to elucidate the electrochemical behaviour of Cu(2+) at these electrodes in a variety of supporting electrolytes. For all of the electrolytes studied the anodic peaks, obtained on the reverse scans, showed that the Cu(2+) had been deposited as a thin layer on the surface of the SPCE. The anodic peak of greatest magnitude was obtained in 0.1 M malonic acid. The possibility of determining Cu(2+) at trace levels using this medium was examined by differential pulse anodic stripping voltammetry (DPASV). The effect of Bi(3+), Cd(2+), Fe(3+), Hg(2)(2+), Pb(2+), Sb(3+) and Zn(2+) on the Cu stripping peak was examined and under the conditions employed, only Hg(2)(2+) was found to significantly effect the response gained. The sensors were evaluated by carrying out Cu(2+) determinations on spiked and unspiked serum and water samples. The mean recovery was found in all cases to be >90% and the performance characteristics indicated the method holds promise for trace Cu(2+) levels by employment of Hg-free SPCEs using DPASV.
authors.affiliation: Centre for Research in Analytical, Materials and Sensors Science, Faculty of Applied Sciences, University of the West of England, Bristol, Frenchay Campus, Coldharbour Lane, Bristol BS16 1QY, UK.
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Honeychurch
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Hawkins
authors.forename: John P
authors.initials: JP
authors.lastname: Hart
authors.forename: David C
authors.initials: DC
authors.lastname: Cowell