Renewable Drops Electrochemical Sensor for Sulfide Ions Detection

Abstract

The design and characteristics of a novel electrochemical system, which uses a drop as a renewable electroanalytical sensor, are described. This article describes the performance of the electrochemical system, the coupling of the experimental arrangement with flow injection technique and a demonstration of its applicability for the measurement of sulfide. The method is based on renewable drops of ferricyanide ions, buffered by borate. The ferrocyanide ions, product of the reaction between ferricyanide and sulfide ions, are oxidized on a platinum microelectrode and the current measured is related to sulfide concentration. The measurements can be done in continuous or static flow mode. In continuous mode, the detection limit is 5.0 Â 10 À5 mol L À1 .

Electrochemical sensors: a powerful tool in analytical chemistry

“…The versatile, economic and very sensitive electrodes are applied for quantification of several organic and inorganic compounds. Stradiotto and co-workers 144 have also used microelectrodes applied to small volumes. An example is shown in Figure 4, where the detection of sulfide ions on renewable drops of ferricyanide ions is obtained on a platinum microelectrode.…”

“…An example is shown in Figure 4, where the detection of sulfide ions on renewable drops of ferricyanide ions is obtained on a platinum microelectrode. 144 The potential for use of UME in biological fluids has been dramatically increased with chemical modifications, such as ion-exchange polymers that have made their applicability in biological fluids more viable. 7,15,145,146 The charged membranes are selective for specific ions and reduce the interference of proteins and other materials indigenous to the physiological system.…”

Controlled‐Potential‐Based Electrochemical Sulfide Sensors: A Review

“…The research carried out by Milani et al. demonstrated that a platinum microelectrode and a drop are appropriate for sulfide determinations in electroanalytical systems [97] . Depending upon the sulfide ion oxidation by ferricyanide, they proposed an arrangement for FIA to evaluate sulfide concentration in aqueous solution.…”

Highly Stable Polymeric Ionic Liquid Modified Electrode to Immobilize Ferricyanide for Electroanalysis of Sulfide

“…Nonetheless, even with its low solubility in water, it is difficult to retain the long-term stability of the RTIL thin film. In this study, we report an easy and reliable method to improve the stability of the RTILmodified electrode by preparing a hydrophobic IL polymer film cross-linked between 1-butyl-3-vinylimidazolium hexafluorophosphate ([C 4 Vim][PF 6 ]) and 1,9-di(3-vinylimidazolium)nonane hexafluorophosphate ([C 9 (Vim) 2 ][PF 6 ] 2 ) on the surface of SPCE. A redox mediator, Fe(CN) 6 …”

“…Since Fe(CN) 6 3À was proved an effective redox mediator for the electrochemical sensing of sulfide in neutral media [3][4][5][6], the as-prepared Fe(CN) 6…”