Copper Film Modified Glassy Carbon Electrode and Copper Film with Carbon Nanotubes Modified Screen-Printed Electrode for the Cd(II) Determination

Abstract

A copper film modified glassy carbon electrode (CuF/GCE) and a novel copper film with carbon nanotubes modified screen-printed electrode (CuF/CN/SPE) for anodic stripping voltammetric measurement of ultratrace levels of Cd(II) are presented. During the development of the research procedure, several main parameters were investigated and optimized. The optimal electroanalytical performance of the working electrodes was achieved in electrolyte 0.1 M HCl and 2 × 10−4 M Cu(II). The copper film modified glassy carbon electrode exhibited operation in the presence of dissolved oxygen with a calculated limit of detection of 1.7 × 10−10 M and 210 s accumulation time, repeatability with RSD of 4.2% (n = 5). In the case of copper film with carbon nanotubes modified screen-printed electrode limit of detection amounted 1.3 × 10−10 M for accumulation time of 210 s and with RSD of 4.5% (n = 5). The calibration curve has a linear range in the tested concentration of 5 × 10−10–5 × 10−7 M (r = 0.999) for CuF/GCE and 3 × 10−10–3 × 10−7 M (r = 0.999) for CuF/CN/SPE with 210 s accumulation time in both cases. The used electrodes enable trace determination of cadmium in different environmental water samples containing organic matrix. The validation of the proposed procedures was carried out through analysis certified reference materials: TM-25.5, SPS-SW1, and SPS-WW1.

Keywords

• copper modified electrode
• carbon-based electrode materials
• screen-printed electrode
• electrochemical detection
• stripping voltammetry
• cadmium determination