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Voltammetry, which is at the core of electroanalytical chemistry, is an analytical method that investigates and evaluates the current-potential relationship obtained at a given working electrode. If it is used dropping mercury as working electrode, the method is called as polarography. The current year 2022 marks the 100th anniversary of the discovery of polarography by Czech Jaroslav Heyrovský. He received the Nobel Prize in Chemistry in 1959 for this discovery and his contribution to the scientific world. A hundred years, within the endless existence of the universe is maybe nothing. A hundred years, in the history of mankind is a line, maybe a short paragraph. But, in science, a hundred years can lead to very significant advances in a field and often to the birth and establishment of an entirely new scientific discipline. Indeed, in the last hundred years, the design and use of new electrochemical devices, depending on the progress in microelectronics and computer technologies, has almost revolutionized voltammetry. Besides these developments, due to the fact that the redox (oxidation/reduction) process is very basic for living organisms; the voltammetry, especially with the beginning of the 21st century, has started to be used as a very powerful tool in neuroscience to solve the mystery of the brain (the basic problems of biomolecules with physiological and genetic importance in brain tissue). This review article is an overview of the 100-year history and fascinating development of voltammetry from Heyrovský to the present. [ABSTRACT FROM AUTHOR]

In this investigation, a novel electrochemical approach employing a bare carbon paste electrode (CPE) has been devised for the sensitive and expeditious quantification of the tyrosine kinase inhibitor vandetanib (VAN). VAN, a pivotal anti-tumor agent employed in various cancer types, notably medullary thyroid cancer, manifested an irreversible oxidation peak at approximately +1.17 V (vs. Ag/AgCl, 3 M NaCl) in 0.1 M HNO3, elucidated through cyclic voltammetry. The electrode reaction was determined to proceed via controlled adsorption. The study meticulously examined the influence of anionic surfactant sodium dodecyl sulfate (SDS), instrumental parameters, pH fluctuations, and the composition of the supporting electrolyte on the oxidation peak of VAN. Remarkably, the sensitivity of stripping voltammetric measurements markedly augmented upon the inclusion of 9 × 10−4 M SDS. Employing optimized parameters for SW-AdSV (square-wave adsorptive stripping voltammetry), the bare CPE demonstrated exceptional linearity within the dynamic ranges of 1.05×10−7 – 1.6×10−5 M for VAN. The limit of detection and limit of quantification were established at 2.7×10−8 and 9.0×10−8 M for VAN, respectively. Furthermore, the developed electrochemical methodology was effectively applied for the detection of VAN in spiked model serum samples. [ABSTRACT FROM AUTHOR]

Selective serotonin reuptake inhibitors (SSRIs) are commonly used to treat depression. SSRIs are classified as fluoxetine, paroxetine, escitalopram, citalopram, sertraline, and fluvoxamine. Several methods have been published for the determination of SSRI drugs in pharmaceuticals, biological materials and environmental samples. This review covers the analytical methods described in the literature for the determination of SSRIs and their main metabolites or some compounds belonging to the same SSRI group. The analytical methods are generally chromatography based methods coupled to different detectors, electroanalytical methods, capillary zone electrophoretic methods, and spectrometric methods.

The electrochemical properties of thiourea (TU) were investigated in pH range 2.0–12.0 by cyclic and square-wave voltammetry. The compound was irreversibly oxidized at a pencil graphite electrode in one or two oxidation steps which are pH-dependent. Based on the voltammetric peak for the second oxidation process of TU in phosphate buffer at pH 12.0, a square-wave voltammetric method was proposed for the determination of the compound in the range 6.3–30μm, with a detection limit of 1.29μm. The applicability to direct assays of wastewaters was also tested.