Chromatographic determination of chromium(VI) with coulometric detection based on the electrocatalysis by adsorbed iodine of the reduction at platinum electrodes in acidic solutions

Abstract

Adsorbed iodine at a Pt electrode is demonstrated to be anelectrocatalyst for the irreversible electrochemical reduction of Cr(V1) in HCI and H2S04 solutions. Determination of Cr(V1) in a coulometric flow-through electrode is possible in the range 0.4 ng to 80 pg. No interference by dissolved 0, is observed. Application of the coulometrlc detector for chromatographic determinations of Cr(V1) Is presented.

Application of chelate-forming resin and modified glassy carbon electrode for selective determination of iron(III) by liquid chromatography with electrochemical detection

“…The majority of metal cations would have to be determined via reduction steps that at common electrode materials frequently introduce problems associated with oxygen interference, electrode stability, and/or the effects related 0003-2700/87/0359-2776S01.50/0 © 1987 American Chemical Society to the history of its use. Deliberate modification of the indicator surface with the durable, selective, and sensitive coatings might be, in this context, advantageous (16)(17)(18)(19)(20). A remarkable success in the early work with inorganic films, namely with mixed-valent metal cyanide complexes (21-27), is encouraging.…”

Electroanalytical sensing of chromium(iii) and (vi) utilising gold screen printed macro electrodes

“…5,6 Currently available techniques for the detection of chromium (VI) fall in to two distinct categories; direct and indirect detection. Chromatography, 7,8 extraction, 9,10 and co-precipitation 11,12 are techniques which all require prior separation, which increase detection costs, time and accessibility. Each of the indirect methods also suffer from chromium(III) interference, often found in relatively high concentrations within natural samples.…”

Iodide Modified Silver Electrode and Its Application to the Electroanalysis of Hemoglobin

“…This complex could directly reduce the oxidized form of cytochrome c, indicating that the surface of a iodide modi®ed silver electrode might have some special properties which aids electron transfer between protein and silver. Facilitation of oxidation/reduction for substances, such as Cr(VI) [20], Pt(II) [21], and ascorbic acid [22], at metallic surfaces modi®ed with iodide traces back to the pioneering work of D. C. Johnson [20,23] and others [21,22]. Such a iodide modi®ed silver electrode was employed in this work to study the electrochemistry of hemoglobin.…”