Electrochemical preconcentration of metals using mercury film electrodes followed by electrothermal vaporization into an inductively coupled plasma and determination by atomic emission spectrometry.

Abstract

The production and use of mercury film electrodes for matrix separation and preconcentration of trace metals from biological materials prior to their determination by inductively coupled plasma atomic emission spectrometry (ICP-AES) are described. Separation and preconcentration are achieved by controlled potential electrolysis on mercury-plated, glassy carbon electrodes. Electrodes with trace metal amalgam are transferred to an electrothermal vaporization device, the mercury is removed by evaporation, and the metals are then evaporated and determined simultaneously by ICP-AES. The method is applied to the determination of eight trace elements, Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn, in water solution and in the biological standard reference materials urine and bovine liver. The method precision varied between 3.8 and 8.1%.