Copper adhesive-tapes for the assembly of electrodes and miniaturized cells for the detection of nitrates, nitrites and glucose

A simple and replicable approach based on the use of a cutting plotter is here presented for assembling copper electrodes by adopting adhesive copper tapes. The behavior of these Cu adhesive-tape electrodes thus assembled was first compared with that of commercial Cu-disk electrodes in conventional cells. This comparison led to completely coincident results, even if in both cases it was necessary to subject the surface of copper electrodes to an electrochemical pre-treatment. Subsequently, a quite similar approach was used to build miniaturized electrochemical cells suitable for the analysis of microvolumes of samples where reference and counter electrodes were pencil drawn. In order to evaluate thoroughly the performance of these Cu adhesive-tape electrodes, they were adopted for the nonenzymatic determination of glucose in basic medium and for the detection of nitrates and nitrites in acid medium by achieving totally satisfactory findings. The miniaturized electrochemical cell was instead successfully used only for the detection of glucose in a basic medium, since the detection of nitrates and nitrites in an acid medium required preliminary deaeration to remove atmospheric oxygen, which is an impossible operation in the miniaturized electrochemical cell. This glucose detection was also performed in a real sample consisting of a rehydration solution purchased from a local pharmacy. This paper reports the satisfactory results found in this investigation.