The polarographic and voltammetric behaviour of the copper(II) mitoxantrone complex and its analytical application.

The polarographic and voltammetric behaviour of the copper(II)-mitoxantrone complex have been studied. A well-defined linear sweep voltammetric peak was obtained at -0.275 V (vs. Ag AgCl ) or -0.325 V (vs. SCE) in ammonia-ammonium chloride (20 mmoll(-1), pH 9.0). The characteristics of the peak have been examined in detail. The experimental results show that the reduction of the copper(II) mitoxantrone complex is irreversible and the peak displays adsorption characteristics at the dropping mercury electrode. A mechanism is proposed for the reduction of the complex, comprising one-electron reduction of the copper(II) of the complex, is reduced directly in the complex form. A single-sweep oscillopolarographic method was develped for the determination of copper(II). The peak current is proportional to the concentration over the range 5 x 10(-8)-2 x 10(-5) mol l(-1). The method reported here has the advantage that the interference of many common metal ions is small.