Voltammetric Study of Aminopurines on Pencil Graphite Electrode in the Presence of Copper Ions

Abstract

Electrochemical oxidations of aminopurines (adenine, 2-aminopurine, 2,6-diaminopurine) and their complexes with Cu(I) on a pencil graphite electrode were investigated by means of linear sweep voltammetry (LSV) and elimination voltammetry with linear scan (EVLS). The anodic process of the Cu(I)-aminopurine complex, corresponding to the oxidation of Cu(I) to Cu(II), takes place in the potential range between 0.4 and 0.5 V (vs. Ag/AgCl/3 M KCl). At more positive potentials the aminopurines provide voltammetric peaks resulting from the oxidation of the purine ring. The stability of the accumulated complex layer was investigated by the adsorptive transfer stripping technique.

A Pencil Graphite Electrode In Situ Modified by Monovalent Copper: a Promising Tool for the Determination of Methylxanthines

“…In the case of Xan a double voltammetric signal (I Cu,ox ) appeared, which is in accordance with recently published results [20]. Moreover, new signals appeared at more negative potentials corresponding to the oxidation of the copper complex with Xan or mXans (I Cu,Com ), whose mechanism was suggested elsewhere [18,19]. Compared to other derivatives, voltammetric sigScheme 1.…”

“…These methods proved to be suitable for the study of these processes because of their simple instrumentation and an undemanding design, which consists particularly in a very low consumption of the substances monitored, the use of small volumes of detection and a low cost [19,20]. The EVLS procedure is based on the mathematic transformation of voltammetric curves and makes use of the fact that the whole voltammetric current consists of partial current components (charging, kinetic and diffusion), and each of them is differently dependent on scan rate.…”

“…Sensitivity-enhanced voltammetric detection of mXans was achieved by forming of complex with Cu(I) and application of elimination proce-positive potentials (ca. 0.4 V) due to the oxidation of the Cu(I)-purine complex, which had been formed at the electrode at a sufficient starting potential and accumulation time [12,17,19]. The latter peak corresponded to the oxidation of the basic purine structure and its position was related to the voltammetric signal obtained in the absence of Cu(II).…”

Guanine oxidation signal enhancement in single strand DNA with polyacrylonitrile/polyaniline (PAN/PAni) hybrid nanofibers

“…Differential pulse voltammetry (DPV) measurements were performed with a PGSTAT204 digital potentiostat/galvanostat using NOVA software package (Eco Chemie). The three electrode system consisted of a NFs‐coated PG as the working electrode, a reference electrode (Ag/AgCl), and a platinum wire as the auxiliary electrode, and a Rotring T 0.5 pencil was used as the holder for the graphite lead (Tombo HB model 0.5 mm) . Electrical contact with the lead was obtained by soldering a metallic wire to the metallic part.…”

pH-controlled voltammetric behaviors and detection of phytohormone 6-benzylaminopurine using MWCNT/GCE

“…However, because of toxicity of mercury, it is highly desired to explore other ''green'' electrode materials. In the stripping voltammetric detection of 6-BAP, different carbon materials such as pencil graphite [23], carbon nanotubes [20], acetylene black-dihexadecyl hydrogen phosphate [21], and ordered mesoporous carbons [17] had been used for the fabrication of modified electrodes. However, to our best knowledge, there is no report on the voltammetric behaviors for the electrochemical oxidation of 6-BAP under the different pH conditions.…”