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CVSIM in the Literature
Links to papers that used the program CVSIM and/or CVFIT
Kinetic study of the oxidation of some catecholamines by digital simulation of cyclic voltammograms
Electrochemical oxidation of some catecholamines such as dopamine (1), L‐dopa (2), and methyldopa (3) has been studied in various pH values, using cyclic voltammetry. The results indicate participati...
Electrochemical nitration of catechols: Kinetic study by digital simulation of cyclic voltammograms
Electrochemical nitration of catechols has been studied in the presence of nitrite ion as nucleophile in aqueous solution, by means of cyclic voltamme…
Redox Mediation and Photomechanical Oscillations Involving Photosensitive Cyclometalated Ru(II) Complexes, Glucose Oxidase, and Peroxidase
Intact photosensitive cyclometalated RuII derivatives of 2-phenylpyridine or N,N-dimethylbenzylamine cis-[Ru(C∼N)(LL)X2]PF6 [C∼N = o-C6H4-py or o-C6H4CH2NMe2; LL = 1,10-phenanththroline (phen), 2,2‘-bipyridine (bpy), or 4,4‘-Me2-2,2‘-bipyridine (Me2bpy); X = MeCN or pyridine (py)] are efficient mediators of glucose oxidase (GO) from Aspergillus niger and horseradish peroxidase (HRP). Their redox potentials in an aqueous buffer are in the range 0.15−0.35 V versus SCE, and the rate constants for the oxidation GO(red) (where red indicates reduced) by the electrochemically generated RuIII species equal (1.7−2.5) × 106 M-1 s-1 at pH 7 and 25 °C. The redox potentials of all complexes decrease cathodically by 0.4−0.6 V upon irradiation by visible light because of the photoinduced solvolysis of acetonitrile or py ligands. These in situ generated species display an even better mediating performance with HRP, although their behavior toward GO is different. The loading of a ruthenium unit into the protein interior brings about large catalytic currents in a self-assembled system GO−Ru−d-glucose. The estimated rate constant for intramolecular electron transfer from FADH2 of the active site at RuIII, kintra, equals 4.4 × 103 s-1. This suggests that the distance between the redox partners is around 19 Å. The value of 21 Å was obtained through the docking analysis of a possible closest-to-FAD localization of a Ru-containing fragment derived from the irradiated complex cis-[Ru(o-C6H4-py)(phen)(MeCN)2]PF6. The operational stability of the GO−Ru assemblies depends on the nature of complex used, the highest being observed for cis-[Ru(o-C6H4-py)(Me2bpy)(MeCN)2]PF6 (2). UV−vis studies of interaction of 2 with GO revealed photomechanical oscillations in the system GO−Ru−d-glucose. When irradiated complex 2 is mixed with GO and d-glucose, the absorbance at 510 nm increases because of the enzymatic reduction of RuIII to RuII. The absorbance drops rapidly and then increases as in the first cycle after shaking the reaction solution. Many cycles are possible, and the rate of absorbance increase does not depend on a cycle number. A plausible mechanism of the oscillations is presented.
Investigation of the electrochemical behavior of some catecholamines in the presence of 4-aminobenzoic acid
Electrochemical oxidation of some catecholamines such as dopamine (1), l-dopa (2) and methyldopa (3) has been studied in the presence of 4-aminobenzoi…
Redox equilibria of the nitrosonium cation and of its nonbonded complexes
The electrochemical oxidation of 2,6-dichloro-1,4-phenylenediamine
The electrochemical oxidation of 2,6-dichloro-1,4-phenylenediamine was studied at a glassy carbon electrode in a 50 vol% methanol—water mixture contai…
The effect of solvent on the electrode process of methylcobalamine as studied by cyclic voltammetry
The cyclic voltammetry (CV) of methylcobalamine, Me–Cbl, was investigated as a function of solvent with different ratios of DMF/MeOH and for neat N,N-…
Electrochemical Monitoring of Valence Bond Isomers Interconversion in Bipyridyl-C61 Anions
Electrochemical study of methylcobalamin Determination of the reduction potential for a quasireversible system with a fast following reaction
The reductive electrochemistry of methylocobalamin in nonaqueous solution is typical of many electrochemical mechanisms in that the initial electron t…
Electrocatalytic reduction of organohalides mediated by the dihalo-molybdenum phosphinic complexes
trans
-[MoX
2
(Ph
2
PCH
2
CH
2
PPh
2
)
2
] (X = I, Br)—A mechanistic study by cyclic voltammetry digital simulation†
Kinetic Study of the Oxidation of Catechols in the Presence of N-Methylaniline
UV-Visible Spectrooelectrochemistry of the Reduction Products of Anthraquinone in Dimethylformamide Solutions: An Advanced Undergraduate Experiment
The redox properties of anthraquinone (AQ) may be used to model the behaviour of quinones in biological systems. AQ undergoes two successive one-electron reductions in aprotic solvents to form a stable radical anion (AQ.-) and a stable dianion (AQ2-) but this behaviour is altered in the presence of a proton donor. This advanced undergraduate experiment shows how cyclic voltammetry, digital simulations of cyclic voltammograms, and UV-visible spectroelectrochemistry may be used to examine the reduction behaviour of AQ in dimethylformamide (DMF), both in the absence and presence of benzoic acid.The cyclic voltammetry of AQ in DMF shows two reversible one-electron reductions. This allows the UV-visible spectra of AQ.- and of AQ2- to be determined using an optically transparent thin layer electrode (OTTLE) cell. AQH- may also be detected in the spectra if there are proton impurities. When benzoic acid is added to the DMF, the cyclic voltammograms are markedly altered with almost all the reduction occurring near the AQ/AQ.- potential and the corresponding oxidation at rather more positive potentials. The UV-visible spectroelectrochemistry shows AQH2 as the stable reduction product under these conditions while digital simulations of the cyclic voltammograms support a mechanism involving protonation of AQ.- followed by AQH. disproportionation.
Evidence for a Michaelis−Menten Type Mechanism in the Electrocatalytic Oxidation of Mercaptopropionic Acid by an Amavadine Model
The amavadine complex and its model [VL2]2- (L = -ON[CH(CH3)COO-]2 (HIDPA3-) or -ON(CH2COO-)2 (HIDA3-), respectively) undergo, in aqueous medium and at a Pt electrode, a fully electrochemical and chemical reversible Viv/v oxidation and act as electron-transfer mediators in the electrocatalytic oxidation of some thiols (HSR) such as HS(CH2)nCOOH (n = 1 or 2, i.e, mercaptoacetic or mercaptopropionic acid, respectively) and HSCH2CH(NH2)COOH (cysteine) to the corresponding disulfides (RS-SR) which were isolated upon bulk preparative electrolyses. As shown by digital simulation of cyclic voltammetry, this redox catalysis process occurs through an unprecedented mechanism involving Michaelis−Menten type kinetics with formation (k1 = 1.2 × 103 M-1 s-1) of an intermediate species (with half-life time of ca. 0.3 s) derived from the interaction of the oxidized vanadium complex (the active form of the mediator) with the substrate. A possible biological role for amavadine is suggested by these results.
Estimation of homogeneous rate constants of reaction of electrochemically generated ortho‐benzoquinones with 1,3‐indandione
Electrochemical oxidation of some catechol derivatives has been studied in the presence of 1,3‐indandione as nucleophile in aqueous solution, by means of cyclic voltammetry and controlled‐potential c...
Two-equivalent electrochemical reduction of a cyano-complex [TlIII(CN)2]+ and the novel di-nuclear compound [(CN)5PtII−TlIII]0
Two-equivalent electrochemical reduction of a cyano-complex [TlIII(CN)2]+ and the novel di-nuclear compound [(CN)5PtII−TlIII]0
cyclic.pdf
Electron-transfer kinetics and ternary equilibria of the nitrogen dioxide(1+)/nitrogen dioxide/dinitrogen tetraoxide system by transient electrochemistry.pdf
cyclic.pdf
cyclic.pdf
Electrochemistry of the bis(1,4,7-triazacyclodecane) cobalt(III) complex and its role in the catalytic reduction of hydrogen
The electrochemistry of the bis(1,4,7-triazacyclodecane) cobalt(III) complex at a mercury electrode, HMDE, in aqueous Britton–Robinson buffer solution…
Kinetic and Mechanistic Investigation of Electrochemical Oxidation of Hydroquinones in the Absence and Presence of 2-acetyl-gamma-butyrolactone - Mohsen Ameri, Alireza Asghari, Ali Amoozadeh, Davood Nematollahi, Mansour Arab Chamjangali, Leila Boutorabi, 2014
Electrochemical oxidation of hydroquinones (1a,b) was studied in the presence of 2-acetyl-gamma-butyrolactone (3) as nucleophile in phosphate buffer solution (p...
The effect of solvent on the electrode process of methylcobalamine as studied by cyclic voltammetry
The cyclic voltammetry (CV) of methylcobalamine, Me–Cbl, was investigated as a function of solvent with different ratios of DMF/MeOH and for neat N,N-…
Voltammetric study of the oxidation of quercetin and catechin in the presence of cyanide ion
The reaction of electrochemically generated o-benzoquinones from oxidation of quercetin and catechin as Michael acceptors with cyanide ion as nucleophile has been studied using cyclic voltammetry. The reaction mechanism is believed to be EC; including oxidation of catechol moiety of these antioxidants followed by Michael addition of cyanide ion. The observed homogeneous rate constants (k obs) for reactions were estimated by comparing the experimental voltammetric responses with the digitally simulated results based on the proposed mechanism. The effects of pH and nucleophile concentration on voltammetric behavior and the rate constants of chemical reactions were also described.
A cyclic voltammetric study of mangano(II)undecatungstosilicate: an illustrative example of the reduction, protonation and disproportionation pathways of transition metal substituted heteropolytungstates in aqueous solution
Mangano(II)undecatungstosilicate [(H2O)MnSiW11O39]6− was studied by cyclic voltammetry in aqueous solution at various pH values. The pH-dependent wave…
Ligand substitution at 19-electron organometallic centers. Electrocatalytic CO substitution reactions of (methylcyclopentadienyl)Mn(CO)2NO+ and (indenyl)Mn(CO)2NO+
(Methylcyclopentadienyl)Mn(CO)NO+ (1+) undergoes a one-electron reduction at an electrode to give a 19-electron neutral radical that rapidly dissociat…
Influence of micelles and microemulsions on one-electron reduction of 1-alkyl-4-carbomethoxypyridinium ions
Diffusion, heterogeneous kinetics, and radical stability were studied for one-electron reductions of 1-methyl- and 1-hexadecyl-4-carbomethoxypyridiniu…
Electrochemical oxidation of acetaminophen in the presence of diclofenac and piroxicam - Synthesis of new derivatives and kinetic investigation of toxic quinone imine/drugs interactions
In this research, electrochemical oxidation of acetaminophen was investigated in the presence of steroidal anti-inflammatory drugs diclofenac and piro…
The Reductive Cleavage Mechanism and Complex Stability of Glutathionyl‐Cobalamin in Acidic Media
Reactivity of 17-, 18-, and 19-electron cationic complexes generated by the electrochemical oxidation of tricarbonyl(mesitylene)tungsten
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