Simple, Fast and Sensitive Voltammetric Procedure for Copper Ion Determination Using a Solid Gold Microelectrode Array

The present study reports the application of a gold microelectrode array to determine copper(II) ions by anodic stripping voltammetry (ASV). The microelectrode characterization of the presented working electrode was investigated. Moreover, the way of its preparation ensures its reusability and eco-friendly character, thanks to the use of environmentally benign electrode material. The procedure does not require modification of the surface of the working electrode. Main experimental parameters were optimized, including pH and a concentration of the supporting electrolyte, activation and deposition conditions, and square wave parameters. The calibration graph was linear in the range of Cu(II) concentrations from 2 × 10−9 to 2 × 10−7 mol L−1 (with a deposition time of 30 s) and from 5 × 10−10 to 5 × 10−8 mol L−1 (with a deposition time of 90 s; RSD was 4.7% (n = 3) for a 1 × 10−8 mol L−1 of Cu(II)). The limit of detection was equal to 1.93 × 10−10 mol L−1 (tacc = 90 s). The correctness of the developed procedure was successfully checked by analysis of certified reference material and a tap water sample, confirming the possibility of its practical application. Satisfactory recovery values were also obtained during the analysis of an environmental water sample.