Modern Electrochemical Methods Research Articles

ПОРІВНЯЛЬНА ХАРАКТЕРИСТИКА ЕФЕКТИВНОСТІ ЕЛЕКТРОХІМІЧНИХ МЕТОДІВ ДОСЛІДЖЕННЯ ВМІСТУ ВАЖКИХ МЕТАЛІВ У СТІЧНИХ ВОДАХ

Сompare the various modern electrochemical research methods effectiveness used to determine the heavy metals concentration in waste water, based on the literature data. Methodology. Analysis of literature data on the possibilities, advantages and disadvantages of voltammetric, potentiometric, coulometric and conductometric methods for the heavy metals content studying in waste water. Findings. The electrochemical methods are the most common methods for analyzing the composition of waste water. Among their advantages, it should be noted high selectivity, low concentration registration limit (up to 10-10 M for stripping voltammetric methods), simplicity in execution, absence of preliminary long-term samples preparation for analysis, the ability to microvolumes measure without samples destroying and automation of the process for continuous metals concentrations determination in waste water treatment, relatively inexpensive equipment, the ability to determine the concentration of several metal ions in a mixture. Originality. The studies have shown that most often the concentration of heavy metals in waste water determine with the using of the different modifications of voltammetric research methods (polarography and varieties of stripping voltammetry) and potentiometric research methods in particular with highly sensitive and specific ion-selective indicator electrodes. Practical value. The theoretical material on modern electrochemical methods for the heavy metal ions content determining in waste water is generalized.

Conference Modern Electrochemical Methods XXXVI, Czech Republic, 2016

Conference Modern Electrochemical Methods XXXVI, Czech Republic, 2016

Guest Editorial, Petr Zuman 90th Birthday Issue

Guest Editorial, Petr Zuman 90th Birthday Issue

Conference XXXVth Modern Electrochemical Methods, Czech Republic, 2015

This Special Issue of Chemical Monthly is dedicated to lectures presented at an international conference which took place in May 2015 in the Czech Republic: XXXVth Modern Electrochemical Methods (MEM; May 18–22, 2015, in Jetrichovice). This meeting belongs to the traditional series of conferences started in 1980 in Mezni Louka, Czech Republic (moreover, some conferences of this name were organized before but they were not included into the numbered series). Since 1980, MEM conferences have been organized annually (with only one exception in 1989). Particular events of this series were held at various places of the Czech Republic (e.g., Bedrichov, Mezni Louka, Trojanovice, Harrachov). However, Jetrichovice near Decin (‘‘Bohemian Switzerland’’ in the west-northern part of the Czech Republic) has become the favorite venue among regular MEM participants and the last 16 years of the MEM were organized almost exclusively there (with only two exception in 2001 and 2002). The XXXVth MEM conference comprised 65 lectures fitting into its general topics, devoted to progress in electrochemistry of organic and bioactive compounds, including contributions oriented towards studies of mechanisms of electrochemical processes involving reducible or oxidizable organic species, development of novel materials for construction of working electrodes and electrochemical (bio)sensors, as well as analytical techniques designed for the determination of biologically active compounds (such as toxic substances or drugs) in various matrices. Attention was paid to electrochemical analysis of biopolymers, their labeling with redox active species and prospective utilization in novel diagnostic approaches. This issue contains 30 original papers from lectures presented at the XXXVth MEM. These articles comprise a representative selection of contributions covering the above topics of this year’s conference. As Editors of this special issue, we would like to express our gratitude to the Editor-in-Chief of the journal, Peter Gartner, and to the Managing Editor, Christian Hametner, for their assistance and cooperation, and to the staff of the Publisher, Springer Vienna, for their contribution to the special issue release. We are very glad that this special issue is the second in the order, devoted to the series of Modern Electrochemical Methods conferences. The first one was composed of the selected best contributions from the conference XXXIVth MEM (2014). Let us to express our hope that this is the start of a new, long and strong tradition. Last but not least, we thank all authors for their great effort to contribute with results of their research, and all referees for valuable comments that helped to improve the quality of the manuscripts. Enjoy reading!

Special Issue on Modern Electrochemical Methods XXXIV and 47th Heyrovský Discussion

Dear colleagues,It is our great pleasure and honor to introduce a special issue of Analytical Letters composed of a selection of papers presented at two international conferences held in May 2014 i...

Electrochemistry of organic, bioactive compounds and biopolymers

This Special Issue of Chemical Monthly is dedicated to lectures presented at two international meetings which took place in May 2014 in the Czech Republic: Modern Electrochemical Methods XXXIV (MEM, May 19–23, 2014, in Jetrichovice) and 47th Heyrovsky Discussion (HD, May 25–29, 2014, in Trest). Both events were parts of traditional conference series. The HD series was initiated in 1967 and it has been organized annually to cover specific topics of electrochemistry and electroanalytical chemistry in particular years. Trest castle in the center of BohemianMoravian Highlands has been the venue where the HD series has been held in the last years with only few exceptions (e.g., in 2012 HD took place in Brno, in 1992 in Bechyne). The first appearance of the MEM conference was in 1980 in Mezni Louka, Czech Republic. Particular events of this series were held at different places of the Czech Republic (e.g., Bedrichov, Mezni Louka, Trojanovice, Harrachov). However, Jetrichovice near Decin (‘‘Bohemian Switzerland’’ in the northern part of the Czech Republic) has become the favorite venue among the regular MEM participants and last 12 years of the MEM were organized there (there has been only two exceptions since the year 2000). By its subtitle, the 47th HD was devoted to Electrochemistry of Organic and Bioactive Compounds. It comprised 25 lectures fitting into the general topics, including contributions oriented towards studies of mechanisms of electrochemical processes involving reducible or oxidizable organic species, development of novel materials for construction of electrochemical (bio)sensors, as well as analytical techniques designed for the determination of biologically active compounds (such as toxic substances, drugs or components of biopolymers) in various matrices. Attention was paid to electrochemistry of nucleic acids and proteins and its applications in biosensing. Interdisciplinary milieu of the meeting was strengthened by incorporation of contributions on organic synthesis of redox-labeled nucleic acids and on general aspects of protein–DNA interactions; both topics are closely related to applications of modern electrochemical techniques in biological research and in medical diagnostics. At the MEM conferences, similar topics were presented regularly and formed a significant part of the MEM XXXIV as well. This issue contains a review on biophysical and electrochemical techniques used for protein–DNA interaction studies (related to 2 lectures presented at the 47th HD), a review on electroanalysis of antioxidants in pharmaceutical dosage forms (related to the lecture presented at the 47th HD) and 13 original papers from 6 lectures at the 47th HD and another 7 lectures presented at the MEM XXXIV. These articles comprise a representative selection of contributions covering the above topics of both conferences. Enjoy reading! & Miroslav Fojta fojta@ibp.cz

Electrochemical Characterization, Detoxification and Anticancer activity of Didodecyldimethylammonium Bromide

Quaternaryammonium compounds (QACs) are cationic surfactants with broad range applications. They enter into aquatic environment through the discharge of sewage effluents and adversely affect the ecosystem due to toxicity. Modern electrochemical methods have been used for characterization and detoxification of an extensively used QAC, didodecyldimethylammonium bromide (DDAB) in a wide pH range. The diffusion coefficient of DAAB was determined by Randles-Sevcik equation. In acidic conditions the electrochemical reduction of DAAB occurred by two electrons and two protons process. However, in neutral medium the overall reduction of DAAB followed electronation-protonation mechanism involving 3e– and 3H+. Although DDAB is toxic yet it is bestowed with cancer preventing ability. Hence, for getting insights into the under-standing of DAAB anticancer effect, its DNA binding parameters has been evaluated.

The use of modern electrochemical methods in the development of corrosion protective coatings

The industrial corrosion research in the past used descriptive methods for the development of corrosion protective coatings. The legal demand of environmentally friendly coatings and customer demand of high-performance coatings requires the understanding of corrosion effects and the protection against these with organic protective layers. Therefore, actual developments of corrosion protective coatings use modern electrochemical methods for a mechanistic understanding of corrosion processes and there protection. This approach promotes a better description of the interaction between a coating and the corrosion mechanism of the substrate, the development of new coatings with known protection mechanism and additionally actual corrosion protective concepts could be optimized. With the Scanning Kelvin Probe (SKP) the corrosion rate at different geometries and conditions of an E-coated sample has been measured, showing an increased corrosion rate up to seven times higher if the electrolyte layer is very thin. Furthermore, simulated disturbances of pre-treated surfaces have been carried out by a local deposition with mineral oils. By means of SKP measurements, their effect on the pre-treatment layer and on a consecutively applied E-coat were discussed. It was shown that these simulated disturbances could be detected from changes in the Volta potential and that they correlate with noise effects on the coating. Utilizing electrochemical impedance spectroscopy (EIS), an easy way will be presented to measure the “network density” as an indicator of the performance of the corrosion protection by a coating in dependence of its curing temperature, thickness, etc. Finally a new “fast corrosion test” has been developed which measures the delaminated area with EIS after a certain fast climate chamber test. This test correlates quite well with the standard climate chamber test, whereas the expenditure of time could be reduced to 4 days instead of 10–12 weeks.

Analytical Tools for Monitoring Arsenic in the Environment

Inorganic arsenic possesses the highest toxicity threat amongst all its forms found in natural groundwater and its mobility in aquatic systems and in the soil is of great environmental concern. Besides their toxicity to humans, arsenate and arsenite are highly toxic to plants. Arsenic can only be transformed into a less-toxic material and becomes a perma- nent part of the environment. Thus, there is a continuing need for its monitoring at arsenic-containing sites where it occurs naturally at elevated levels. This report reviews technologies with the potential to measure and monitor arsenic in the en- vironment. However, we focus on the modern electrochemical methods of arsenic detection in drinking water. The pros and cons of such techniques are discussed with respect to their sensitivity, ability to detect the chemical states of arsenic, reliability, potential interferences, and ease of operation. In particular, emphasis has been devoted to more recent topics including modern stripping voltammetry, electrode modification, nanomaterials, and biosensors. The necessity for field instrumentation, detection and monitoring has also been addressed.

Inductive vs Solvation Effects in Primary Alkyl Amines: Determination of the Standard Potentials

The determination of the standard potential of alkyl primary amines is reported for the first time using the nanosecond equilibrium method. The versatility and accuracy of the method demonstrates that it is not only an alternative to the classical and modern electrochemical methods, but also a powerful tool for quantifying inductive and/or solvation effects in a related family of compounds. Two different trends were observed depending on alkyl chain length. For "short-chain" alkyl primary amines, where the solvation around the amino group is expected to be the same, the standard potential value appears to follow a linear relationship with the number of carbon atoms, which indicates that the methylene group (-CH2-) causes an inductive effect that is responsible for the stabilization of the amine cation radical. Meanwhile, the E(o) rises slightly to a constant potential value 1.500 V for "long-chain" unbranched alkyl primary amines. This interesting result can be explained by a steric inhibition of solvation around the amino group due to a fold of the long alkyl chain following a solvent exclusion mechanism.

Nichtklassische Methoden zum Studium von Struktur und Dynamik elektrochemischer Phasengrenzen

Nonclassical Methods for Studies of Structure and Dynamics of Electrochemical Phase Boundaries A survey of a selection of modern electrochemical methods with special attention to spectroscopic in situ techniques shows tools, which have enabled a remarkable progress in the understanding of electrochemical structures and processes on a microscopic level. Using selected examples with sometimes strong relationship to practical applications the utilisation of the methods is illustrated. Synergistic effects obtained in a coordinated application of various methods are highlighted.

REVIEW: INTERACTIONS OF METAL IONS WITH NUCLEIC ACIDS AND THEIR SUBUNITS. AN ELECTROCHEMICAL APPROACH

Abstract Different electrochemical methods (differential pulse polarography, sweep voltammetry, alternating current voltammetry, chronocoulometry, cyclic voltammetry) can be used to investigate the interactions of metal ions such as osmium tetroxide, platinum complexes, Cu(II), Ni(II), Zn(II), Cd(II), Pb(II) and Eu(III) with DNA, t-RNA and their subunits. Modern electrochemical methods can detect very small perturbations in a double-helical structure as well as the behavior of single stranded (denatured) fragments of nucleic acids. The effectiveness of polarographic methods is comparable to enzymatic techniques which use specific nucleases. The polarographic data can also be used for the quantitative evaluation of the metal ion nucleic acid interactions (e.g., to calculate the association or stability constants and the number of binding sites). Some topics concerning these problems as well as general aspects of metal-nucleic acid interactions are discussed in this review.