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Przegląd wybranych technik woltamperometrycznych wykorzystujących modyfikowane materiały elektrodowe dla potrzeb oznaczania chromu, niklu oraz kadmu

Janeba-Bartoszewicz Edyta, Bieńczak Krzysztof, Karbowska Bożena, Durka Martyna

Przemysł Chemiczny

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2023

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T. 102, nr 5

495--501

PL

Przedstawiono aktualny stan wiedzy z zakresu modyfikacji elektrod na potrzeby woltamperometrycznego oznaczania chromu, niklu oraz kadmu. Przegląd technik woltamperometrycznych stosowanych do oznaczania wybranych metali w elementach środowiska naturalnego z zastosowaniem nowatorskich materiałów elektrodowych obejmuje wiele wyselekcjonowanych źródeł literatury. Analiza danych literaturowych wykazała, że modyfikowana elektroda z najlepszymi właściwościami elektrochemicznymi dla oznaczania chromu(VI) to elektroda sitodrukowana modyfikowana syntezowanymi nanocząstkami złota (SPE-AuNPs) z granicą wykrywalności 3,1·10⁻¹¹ mol/L (oznaczanie prze- prowadzone techniką anodowej woltamperometrii stripingowej (ASV)). Dla oznaczania niklu(II) była to elektroda z węgla szklistego pokryta filmem bizmutu (GCE-BiFE) z granicą wykrywalności 1,7·10⁻⁹ mol/L (oznaczanie przeprowadzone techniką adsorpcyjnej woltamperometrii stripingowej (AdSV)), a dla kadmu(II) elektroda z węgla szklistego modyfikowana polimerem z nadrukowanymi jonami kadmu (GCE/Fe3O4@ SiO2@IIP) z granicą wykrywalności 1,0·10⁻¹⁰ mol/L (oznaczanie przeprowadzone techniką anodowej woltamperometrii stripingowej (ASV)).

EN

A review, with 23 refs., of voltammetric techniques used to det. Cr, Ni and Cd metals in the natural environment with the use of innovative electrode materials. The electrodes with the best electrochem. properties for the detn. of Cr(VI) (screen printing electrode modified with synthesized Au nanoparticles), Ni(II) (glassy carbon electrode covered with a layer of Bi) and Cd(II) (glassy carbon polymer-modified electrode with imprinted Cd ions) were discussed.

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Współczesne podejścia elektrochemiczne do oznaczania arsenu

Ozimek W., Rutkowska I. A., Cox J. A., Kulesza P. J.

Wiadomości Chemiczne

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2015

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[Z] 69, 9-10

809--822

EN

There has been growing interest in development of new methods for the determination of arsenic due to its high toxity and increasing population in the environment. At present, chromatographic (separation) and spectroscopic (detection) approaches are the most common. Although, they are characterized by high sensitivity and low detection limits, the experimental procedures often require generation of toxic AsH3. Electrochemical methods for the determination of arsenic can be considered as complimentary because they are fairly simple and they are subject to different selectivity criteria. In this respect, various stripping voltammetric procedures are becoming popular. The actual stripping voltammetric measurement consists of two steps in which preconcentration of an analyte at the electrode surface is followed by the so called „stripping” step involving electrode reaction recorded in a form of the voltammetric peak. A representative approach involves reduction of the analyte anions upon application of the sufficiently negative potential to form As(0) on the electrode (e.g. gold) surface; this step is followed by voltammetric oxidation (anodic stripping) of the deposit (to As(III)). In a case of so called cathodic stripping voltammetry, the stationary Hanging Mercury Drop Electrode (HMDE) is often used. During the preconcentration step, an insoluble salt is produced on the electrode surface. To facilitate its formation, copper or selenium species are used as mediators. Under such conditions, insoluble Cu3As2 is generated together with copper amalgam on the surface of HMDE. Because sensitivity and detection limit in electroanalytical determinations strongly depend on the current densities measured, there is a need to search for specific catalytic materials that would induce otherwise highly slow and irreversible redox processes of As(III) (oxidation) and, in particular, As(V) (reduction). Designing effective electrocatalytic materials would be of importance to the development of more sensitive stripping methods and monitoring of arsenic under chromatographic and flow conditions. Representative examples of catalytic systems are provided and discussed here. Some attention is also paid to application of enzymes to sensing of arsenic. Electrochemical determination of arsenic(III) is generally better described in literature. Direct determination of As(V) typically requires its binding into chemical compounds. It is reasonable to expect intense research in future aiming at the developing of new electroanalytical methods for direct selective determination of As(V).

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Budowa, właściwości i zastosowania elektrod nano- i mikrostrukturalnych

Krzyczmonik P., Socha E.

Chemik

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2015

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Vol. 69, nr 1

11--18

PL

Artykuł stanowi przegląd zagadnień dotyczących elektrod nano- i mikrostrukturalnych. Przedstawiono problem definiowania nano–i mikroelektrod. Opisano związek rozmiaru elektrody z rodzajem dyfuzji stosowanym do opisu prądu procesu elektrodowego. Omówiono wybrane grupy materiałów wykorzystywane do tworzenia mikroelektrod, oraz przedstawiono wybrane techniki, w których są one stosowane. Omawiano także główne zastosowania nano- i mikroelektrod.

EN

This paper is a review of issues on nano- and microstructure electrodes. The problem of defining micro- and nanoelectrodes has been presented. Moreover, the connection between the size of electrode and the diffusion type used to describe the electrode processes has also been demonstrated. The selected group of materials used to construct microelectrodes has been described and selected techniques in which they are applied have been presented. This paper also discusses the main applications of micro- and nanoelectrodes.