Determination of Trace Amounts of Copper in Tap Water Samples with a Calix[4]arene Modified Carbon Paste Electrode by Differential Pulse Anodic Stripping Voltammetry

Investigating electrochemical deposition of gold on commercial off-the-shelf 3-D printing materials towards developing sensing applications†

The COVID-19 pandemic highlighted the inaccessibility of quick and affordable clinical diagnostics. This led to increased interest in creating low-cost portable electrochemical (EC) devices for environmental monitoring and clinical diagnostics. One important perspective is to develop new fabrication methods for functional and low-cost electrode chips. Techniques, such as electron beam and photolithography, allow precise and high-resolution electrode fabrication; however, they are costly and can be time-consuming. More recently, fused deposition modeling three-dimensional (3-D) printing is being used as an alternative fabrication technique due to the low-cost of the printer and rapid prototyping capability. In this study, we explore enhancing the conductivity of 3-D printed working electrodes with EC gold deposition. Two commercial conductive filament brands were used and investigated to fabricate electrode chips. Furthermore, strategies to apply epoxy glue and conductive silver paint were investigated to control the electrode surface area and ensure good electrical connection. This device enables detection at drinking water concentration thresholds. The practical application of the fabricated electrodes is demonstrated by detecting Cu²⁺ using anodic stripping voltammetry.

Customized electrodes were made with 3-D printing and gold electrochemical reduction towards analytical applications.

Fabrication of novel polymer-modified graphene-based electrochemical sensor for the determination of mercury and lead ions in water and biological samples

Background

This paper presents the application of polyglycine-modified graphene paste electrode (PGMGPE) for the electrochemical detection of Hg (II) and Pb (II) ions in the water and biological samples.

Method

The developed electrode was characterized by field emission scanning electron microscopy. Electrochemical techniques such as cyclic voltammetry and differential pulse voltammetry were used to study the behavior of metal ions.

Results

The modification process improves the electrochemical behavior of heavy metal ions. The peak current varied linearly with the increase of the concentration leading to a detection limit of 6.6 μM (Hg (II)) and 0.8 μM (Pb (II)), respectively.

Conclusion

The developed electrode exhibits good sensitivity, selectivity, stability, and lower detection limit, and was successfully applied to the determination of heavy metal ions in water and biological samples with a good recovery range.

Calixarene-functionalized graphene oxide composites fixed on glassy carbon electrodes for electrochemical detection

Four composite materials were prepared by grafting calixarene derivatives onto the surfaces of graphene oxide (GO) via covalent functionalization to yield covalently functionalized graphene oxides (CFGOs).

Selective electrochemical determination of trace level copper using a salicylaldehyde azine/MWCNTs/Nafion modified pyrolytic graphite electrode by the anodic stripping voltammetric method

Schematic illustration of Cu²⁺in solution detection using a SA/MWCNTs/Nafion modified PGE.

Carbon paste electrodes in the new millennium

In this review (with 500 refs), both electrochemistry and electroanalysis with carbon paste-based electrodes, sensors, and detectors are of interest, when attention is focused on the research activities in the years of new millennium. Concerned are all important aspects of the field, from fundamental investigations with carbon paste as the electrode material, via laboratory examination of the first electrode prototypes, basic and advanced studies of various electrode processes and other phenomena, up to practical applications to the determination of inorganic ions, complexes, and molecules. The latter is presented in a series of extensive tables, offering a nearly complete survey of methods published within the period of 2001–2008. Finally, the latest trends and outstanding achievements are also outlined and future prospects given.