University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Ferricyanide

  • IUPAC Name: iron(3+);hexacyanide
  • Molecular Formula: Fe(CN)6-3
  • CAS Registry Number: NA
  • InChI: InChI=1S/6CN.Fe/c6*1-2;/q;;;;;;-3
  • InChI Key: YAGKRVSRTSUGEY-UHFFFAOYSA-N

@ ChemSpider@ NIST@ PubChem

Citations 15

"Hot-wire Amperometric Monitoring Of Flowing Streams"
Talanta 2000 Volume 50, Issue 6 Pages 1205-1210
Joseph Wang, Markus Jasinski, Gerd-Uwe Flechsig, Peter Grundler and Baomin Tian

Abstract: This paper describes the design of a hot-wire electrochemical flow detector, and the advantages accrued from the effects of locally increased temperature, mainly thermally induced convection, upon the amperometric monitoring of flowing streams. A new hydrodynamic modulation voltammetric approach is presented, in which the solution flow rate remains constant while the temperature of the working electrode is modulated. Factors influencing the response, including the flow rate, temperature pulse, or applied potential, have been investigated. The hot-wire operation results also in a significant enhancement of the flow injection amperometric response. The minimal flow rate dependence observed with the heated electrode should benefit the on-line monitoring of streams with fluctuated natural convection, as well as various in-situ remote sensing applications.
Amperometry Electrode Electrode Electrode Apparatus Optimization

"The Application Of Strongly Reducing Agents In Flow Injection Analysis. 2. Chromium(II)"
Anal. Chim. Acta 1983 Volume 153, Issue 1 Pages 133-139
R. C. Schothorst and G. den Boef

Abstract: Methyl red, o-nitrophenol, IO3-, Fe(CN)63-, UO22+, V(IV) and V(V) can be determined at down to 0.1 mM levels with the Cr(II) - EDTA reagent described in Part I (Anal. Abstr., 1983, 45, 1A8) by measuring the absorbance at 600 nm of the Cr(III) - EDTA produced. Polarographic detection at -1.5 V at a static mercury-drop electrode of the Cr(III) - EDTA resulting from the reduction of NO3- and NO2- affords detection limits for these anions better by factors of 3 and 10, respectively, than with the aforementioned spectrophotometric method.
Spectrophotometry Electrode Polarography

"The Application Of Strongly Reducing Agents In Flow Injection Analysis. 3. Vanadium(II)"
Anal. Chim. Acta 1984 Volume 161, Issue 1 Pages 27-35
R. C. Schothorst, J. J. F. van Veen and G. den Boef

Abstract: This study parallels that of Part II (cf. Anal. Abstr., 1984, 46, 5A6), in which Cr(II) - EDTA was used as reducing agent. Vanadyl sulfate, NH4VO3, K3Fe(CN)6, KIO3, methyl red, uranyl acetate and 2-nitrophenol were determined with spectrophotometric detection at 350 nm, based on the decrease in absorption of the V(II) - EDTA complex. Limits of detection (analyte concentration. for which the absorbance change is 10 times the peak-to-peak noise) range from 0.17 mM to 49 µM. Nitrate, NO2- and NH2OH were determined in alkaline medium with amperometric detection; limits of detection ranged from 15 to 150 µM. Hydrazine was determined at pH 5.7 with amperometric detection (detection limit 95 µM). By using an NH3-detection device coupled to the reduction system, conversions of NO3-, NO2- and NH2OH into NH3 were 26, 54 and 47%, respectively.
Amperometry Spectrophotometry

"Flow Injection Determination Of Oxidants With Leuco-thionine Blue"
Analyst 1988 Volume 113, Issue 7 Pages 1057-1060
armen Martinez-Lozano, Tomás Pérez-Ruiz, Virginia Tomás and Encarnación Yagüe

Abstract: Sample solution (85 µL) is injected into the flow injection system and mixed with leuco-thionine blue solution [prepared by irradiation of thionine blue (C. I. Basic Blue 25) in aqueous EDTA] and buffer solution (pH 4.5 to 5.5) in a reaction coil (100 cm). Flow rates of all solution are 0.74 mL min-1. The absorbance of the solution is measured at 670 nm. Results for determination of IO4-, Cr(VI), Fe(CN)63- and V(V) are presented. Limits of determination ranged from 48 to 0.108 µM. The method was applied in the determination of Cr and V in steels, V in petroleum products and Fe(CN)63- in photographic solution, and in the separation of Cr(VI) - Cr(III) mixtures.
Alloy Crude Product Fixing solution Spectrophotometry Redox

"Liquid Chromatography With Rapid Scanning Electrochemical Detection At Carbon Electrodes"
Anal. Chem. 1983 Volume 55, Issue 12 Pages 1877-1881
W. Lowry Caudill, Andrew G. Ewing, Scott Jones, and R. Mark Wightman

Abstract: Rapid-scanning electrochemical detection for liquid chromatography or flow injection analysis has been investigated with use of a channel-type flow-through cell with a vitreous-carbon or carbon-fiber working electrode. For the separation of seven organic compounds by HPLC on a column (25 cm x 4.6 mm) of Biophase (5 µm) with an aqueous mobile phase (pH 4.1) containing 0.1 M citric acid, 0.14 M NaOH, 0.9 mM Na octyl sulfate and 4.2% of acetonitrile, the detection methods studied were normal pulse, back-step corrected normal pulse and staircase voltammetry. Staircase voltammograms (after background subtraction) gave the most useful results in flowing streams. Detection limits were higher than those achieved with amperometric detection. Rapid-scan electrochemical detection in HPLC, however, permitted more complete identification of organic compounds. The application of rapid-scanning electrochemical detection in the flow injection analysis of K3Fe(CN)6 and of dopamine was also investigated.
HPLC Electrode Electrode Potentiometry Voltammetry Voltammetry

"Thin-layer Spectroelectrochemical Cuvette Cells With Long Optical Path Lengths"
Anal. Chem. 1988 Volume 60, Issue 15 Pages 1645-1648
Yupeng Gui, Steven A. Soper, and Theodore Kuwana

Abstract: The construction and properties are described of thin-layer transmission spectroelectrochemical cells that can be used in a continuous-flow system. For the first cell, a vitreous-carbon block (~2.8 cm x 9.8 mm x 1.7 mm) was placed within a standard spectrophotometric vitreous-silica cell to form the working electrode. Two strips of 125 µm thick PTFE film were fused to the block along the top edges of the cell to provide seals, and a small hole was made in the base of the cell. Surface area of solution contact was ~5.46 cm2. For the second cell, a 1-cm pathlength vitreous-silica cell was used, fitted with Pt-foil working and counter electrodes (each 1 cm x 0.5 cm, 0.1 mm thick) which were bonded to a press-fitted PTFE plug within the cell that defined the effective pathlength (cf. Simone et al., Anal. Abstr., 1983, 45, 1J107). Diagrams are presented to show cell construction and solution flow. Specimen cyclic voltammograms and flow injection analysis response graphs (electrochemical and optical transmission) are presented.
Electrode Spectroelectrochemistry Spectrophotometry Voltammetry Apparatus Flowcell

"Simultaneous Flow Injection Speciation Of Iron(II) And Iron(III) Cyano Complexes Utilizing Electrochemical And Atomic Absorption Detectors In Series"
Fresenius J. Anal. Chem. 1988 Volume 330, Issue 7 Pages 614-618
Emil B. Milosavljevi&#cacute;, Ljiljana Soluji&#cacute;, John H. Nelson and James L. Hendrix

Abstract: The system manifold (illustrated) was constructed from a FIAstar 5020 analyzer. and was equipped with two peristaltic pumps, a 100 µL sample loop and 0.5-mm i.d. tubing, with two detectors in series:(I) a flow-through amperometric cell with platinum working and counter electrodes and a Ag - AgCl reference electrode (separated from the flow stream by an ion-exchange membrane), and(II) an AAS instrument with an air - acetylene flame and hollow-cathode multi-element lamp for measurement of total Fe at 248.3 nm. The carrier stream flow rate was increased from 2.0 to 4.0 mL min-1 between the two detectors. Detector(I), the more sensitive, was used for determination of Fe(CN)64- or Fe(CN)63- by application of a potential of +0.5 or -0.2 V, respectively; corresponding carriers were 10 mM acetate buffer (pH 5.6) or 10 mM Na2CO3. The detection limits were 0.5 µg L-1 of Fe for detector(I) and 0.5 mg L-1 of Fe for(II), and the coefficient of variation were 1.0% (at 40 µg l-1) and 0.4% (at 5.7 mg l-1), respectively. Up to 60 analyzes could be performed in 1 h.
Amperometry Electrode Spectrophotometry Multicomponent Speciation Tecator

"Design And Characterization Of Flow-through Coulometric Cells With Porous Working Electrodes Made Of Crushed Vitreous Carbon"
Fresenius J. Anal. Chem. 1992 Volume 343, Issue 7 Pages 566-575
E. Beinrohr, M. Németh, P. Tschöpel and G. Tölg

Abstract: Three designs (A to C) of cited cell were tested by hydrodynamic and cyclic voltammetry with 10 µM-K4[Fe(CN)6] in KCl solution Nernstian behavior and electrochemical yields of up to 100% were obtained for flow rates of 1 to 7 mL min-1. Cell A involved the Ag - AgCl reference electrode being directly merged into the flowing electrolyte, but required samples and the supporting electrolyte to have similar Cl- concentration. for reliable function. This drawback was removed in cell B, since the reference electrode was separated from the electrolyte by a porous graphite diaphragm. This cell can be used as a detector for flow injection analysis and LC and for pre-concentration. of trace metals. In cell C the counter compartment was hydrodynamically separated from the flowing electrolyte by a non-permeable, electrically conducting cation-exchange membrane (MC 3470). This cell is versatile and its potential uses include the continuous cleaning of electrolytes and electrochemical synthesis. By coating the working electrodes with Hg and removing of dissolved O the background current is reduced, especially in the cathodic region.
Coulometry Electrode Electrode Voltammetry Voltammetry Apparatus Detector

"A Solid Polymer Electrolyte Amperometric Detector For FIA And HPLC With Mobile Phases Of Low Conductivity"
Electroanalysis 1992 Volume 4, Issue 4 Pages 447-451
Lukás Loub, Frantisek Opekar, Vera Pacáková, Karel Stulík

Abstract: The design, construction and operation are described of a flow-through amperometric cell with a small Pt-wire working electrode and sub µL geometric volume and wherein the counter, working and reference electrodes are electrolytically connected by means of a Nafion solid polymer electrolyte. The cell was tested in a flow injection system with use of quinolin-8-ol (I), 4-methylcatechol (II) and K4Fe(CN)6 as model analytes. Calibration graphs were rectilinear from 0.2 to 0.6 µM up to 100 µM. In the determination of I at the 10 and 100 µM levels the coefficient of variation were 4.3 and 1.1% respectively (n = 10). Electrode activity decreased by 10 to 15% during a day's use but this could be restored by cyclic polarization of the working electrode between +1.6 and -0.2 V (vs. Ag - AgCl) for 15 min at 50 mV s-1. The detector has been applied in the HPLC determination of I, catechol and II on a Separon SGX C-18 column (15 cm x 3 mm) with aqueous 4% dioxan as mobile phase. AB An amperometric cell with a small platinum wire working electrode, a submicroliter geometric volume, and a solid polymer electrolyte (Nafion) was constructed and tested. The cell permits sensitive and reliable detection even in mobile phases of negligible elec. conductivity, (e.g., distilled water or nonpolar organic solvents). The sensitivity is substantially higher than that attained with similar cells containing large-area working electrodes; typical limits of detection amt. to analyte concentrations. between 10^-7 and 10^-6 mol/L, corresponding to subnanogram amounts in common HPLC sample volumes The detector response exhibits satisfactory linearity, a linear dynamic range of at least three concentration. decades, and a good precision, with relative standard deviations of 1 to 5%. This cell substantially widens the possibilities of amperometric detection, permitting direct application, for example, to normal-phase HPLC or to methods with programmed composition of the mobile phase (gradient elution).
Amperometry Electrode HPLC Apparatus Linear dynamic range

"A Novel Assembly For Perfluorinated Ion-exchange Membrane-based Sensors Designed For Electroanalytical Measurements In Nonconducting Media"
Electroanalysis 1998 Volume 10, Issue 14 Pages 942-947
Rosanna Toniolo, Nicola Comisso, Gino Bontempelli *, Gilberto Schiavon, Stefano Sitran

Abstract: A perfluorinated ion-exchange membrane-based sensor suitable for electroanal. measurements in electrolyte-free media is described, which was assembled following a novel design enabling an easier preparation procedure. It was fabricated by inserting the terminal portion of a working Pt wire electrode into a Nafion tubing of suitable diameter and welding the wire thus wrapped to the bottom of a cell body by an insulating epoxy resin. The remainder upper part of the working electrode was covered by a Teflon tubing to avoid the elec. contact with the internal electrolyte introduced into the cell body, which was equipped with a counter and a reference electrode. As a result of this configuration, the actual working-electrode surface is the wire circumference contacted by the polyelectrolyte material at the bottom of the assembly which is exposed to the sample. The performance of this sensor was tested by cyclic voltammetry, amperometric monitoring and flow injection analysis for the electroanal. of a series of prototype analytes either dissolved in electrolyte-free water (H2O2, hydroquinone, ferricyanide, I- and Br-) or present in N2 atmospheres (triethylamine and O2). Detection limits for these analytes were estimated (s = 3), together with the corresponding ranges within which the responses display a linear dependence on the analyte concentration. The novel assembly is suitable only for the anal. in electrolyte-free liquid samples, while for the anal. of gaseous atmospheres, especially for flowing gases, ion-exchange membrane sensors prepared by the more usual procedure based on the use of working electrode materials embedded into a moist polyelectrolyte membrane should be preferred.
Sensor Ion exchange Electrode Electrode Nafion membrane Apparatus Detector

"Laser Electrochemical Detection Technique In A Flow System"
Anal. Sci. 1995 Volume 11, Issue 1 Pages 1-8
T. HINOUE, R. HARUI, T. IZUMI, I. WATANABE and H. WATARAI

Abstract: A flow electrolytic cell was described (details given) with a Pt working electrode and a SCE reference electrode. The Pt electrode was illuminated with an intermittent Ar+ laser beam (10 mW at 488 nm) in a flowing solution from the front side of the electrode. The current induced (i) by the illumination was recorded as a function of electrode potential (E) with a lock-in amplifier and was directly observed with an oscilloscope. The cell was charged with sample solutions of K4Fe(CN)6 and K3Fe(CN)6 together with 1 M KCl and 5 mM KCN as supporting electrodes. The log plots of the i-E curves were constructed. The current induced by the laser was proportional to the concentration and strongly dependent on the chopping frequency of the laser and the flow rate. The electron transfer was promoted or depressed by the rise in temperature caused by the laser illumination. The effects of instrumental parameters on the laser detection in the flow system was investigated.
Electrode Spectroelectrochemistry Detector Instrumentation Optimization Laser

"Electrochemistry And Detection Of Some Organic And Biological Molecules At Conducting Poly(3-methylthiophene) Electrodes"
Biosens. Bioelectron. 1991 Volume 6, Issue 4 Pages 333-341
Nada F. Atta, Ahmed Galal, A. Ersin Karagözler, George C. Russell, Hans Zimmer and Harry B. Mark, Jr*

Abstract: Electrodes modified by the electrodeposition of poly(3-methylthiophene) were used as chemical sensors for some organic and biological molecules of industrial and medicinal interest. The electrochemical behaviors of ferri/ferrocyanide, catechol, ascorbic acid, hydroquinone, dopamine, epinephrine, acetaminophen, p-aminophenol and NADH were examined by cyclic voltammetry. The results showed that the proposed modified surface catalyzes the oxidation of these compounds. Differential pulse and square wave techniques were used for the analysis of binary mixture of ascorbic acid with catechol, NADH, dopamine and p-aminophenol. Voltammetric peak resolution was also demonstrated for a ternary mixture of ascorbic acid, catechol and p-aminophenol. Polymer coated electrode was also used in an amperometric detector for flow injection analysis of most of the aforementioned compounds. The responses of the polymer electrode were 4-10 times larger as compared to those of platinum. The modified electrode displayed excellent response stability for successive injections and detection limits were 10 ppb for catechol, dopamine, epinephrine, NADH and p-aminophenol, 1 ppb for acetaminophen and 100 ppb for ascorbic acid. Voltammetric peak positions were affected by the nature of the electrolyte and its pH. Also, film thicknesses were shown to be a factor affecting both the current magnitudes and oxidation peak potential of NADH.
Amperometry Amperometry Electrode Voltammetry Sensor Catalysis pH PPB

"High-speed Flow Injection Determinations Of Oxidative Agents In Aqueous-solutions Based On Reaction With An Online Generated Leuco Dye"
Chem. Tech. 1990 Volume 42, Issue 7 Pages 304-307
MUÊLLER H. ; HANSEN E. H.

Abstract: In a FIAstar 5020 automatic analyzer. (Tecator) with motor-driven injector loop (60 µL), streams (2 mL min-1) of aqueous thionine violet solution (0.2 mg mL-1) and of EDTA solution (3 g in 100 mL of water, diluted to 200 mL with acetate buffer of pH 4.7) were combined and passed through a glass reaction coil (1 m x 2 mm) under a 250-W high-pressure Hg lamp to reduce the dyestuff to its leuco form. Sample solution [e.g., Cr2O72-, Fe(CN)63-, VO3-, S2O82- or Fe3+] was injected into the stream, and the absorbance was measured at 600 nm in a Corning 252 flow-through photometer with a Hellma 178.012 QS flow-through cell (10 mm; 18 µL). Up to 180 samples h-1 can be analyzed. The limit of detection is ~1 µM. As H2O2 reacts only at concentration. of >10 to 100 mM, the determination of, e.g., 10 µM-S2O82- is possible in a 150-fold excess of H2O2.
Spectrophotometry Automation Tecator Injector EDTA Buffer pH Detection limit

"Principles And Applications Of Flow Injection Analysis"
Z. Chem. 1984 Volume 24, Issue 3 Pages 81-93
Helmut Müller, Volkmar Müller

Abstract: Principles of flow injection analysis, including dispersion effects, are described, and the system is discussed in terms of its transport, injection, reaction (e.g., dialysis, dilution, extraction and chemical reaction), detection and data-processing components. An extensive table is presented of applications in clinical, pharmaceutical, water and agricultural chemistry, with details of detection systems and detection limits. Special flow injection methods, e.g., the stopped-flow technique, titration, and closed-system operation, are also discussed. (174 references).
Agricultural Pharmaceutical Clinical analysis Sample preparation Closed loop Dialysis Dilution Dispersion Extraction Review Stopped-flow

"Universal Electrochemical Detector For Flowing Liquids"
Z. Chem. 1990 Volume 30, Issue 11 Pages 419-419
Klaus Bartels

Abstract: The described flow-through cell (for use in, e.g., LC or flow injection analysis) consists of a PTFE block drilled at right-angles with four converging tubular holes to which, by means of interchangeable screw connections, the inlet and outlet tubing and the working and Ag - AgCl reference electrodes are connected. The effective volume of the cell can be altered by the use of electrode mountings of different lengths. The cell was tested by using an ECM 700 electrochemicl measuring system (Zentrum fuer wissenschaftlichen Geraetebau, Berlin), with Pt electrodes (0.5 mm diameter) at 0.8 V vs. Ag - AgCl and at different effective volume (0.5 to 6.3 µL), with K4Fe(CN)6 as analyte in a flow of 1 M KCl at 0.1 and 0.3 mL min-1. Response times were 0.2 to 6.8 s, with rectilinear calibration up to 50 ng and a detection limit of 25 pg.
Electrode Flowcell Detector