Screen printed graphite electrochemical sensors for the voltammetric determination of antimony(iii)

Abstract

The electroanalytical determination of antimony(III) is explored using disposable and economical unmodified screen printed graphite macro-electrodes. These sensors are found to allow the sensing of antimony(III) via anodic stripping voltammetry over the range of 1 to 910 μg L⁻¹ in pH 3.5 acetate buffer solutions with a limit of detection found to correspond to 0.58 μg L⁻¹. The analytical protocol is applied to the sensing of antimony(III) in drinking water samples where a limit of detection was found to correspond to 1.2 μgL⁻¹. The observed detection limits are well below those recommended by the US Environmental Agency and World Health Organisation for antimony(III) concentrations in drinking water. The effects of interferences on the electroanalytical protocol are also explored, where only copper(II) ions are found to be problematic due to the close proximity of the antimony and copper stripping peaks. Proof-of-concept is demonstrated that the interference from copper(II) ions can be eliminated through the application of a complexing agent.