The influence of the halide electrolyte on the electrochemical reduction pathway of some meso-tetrasubstituted porphyrin free bases in N,N-dimethyl formamide

Brett, Christopher M. A.; Brett, Ana Maria C.F. Oliveira

doi:10.1016/0022-0728(88)80014-7

Cited by 4 publications

(6 citation statements)

References 22 publications

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“…The proportions of signals derived from two forms of porphyrin (anion/dianion) also varies depending on the anion of electrolyte salt, which is related to different values of diffusion coefficients of the formed complexes. The dependence of diffusion coefficients on applied supporting electrolyte has been described in [43] . For bromide and borate, the anion radical formation peak (−0.80 V) has higher intensity, whereas in the case of iodide and perchlorate this proportion is reversed.…”

Section: Resultsmentioning

confidence: 99%

Tetraphenylporphyrin as a protein label for triple detection analytical systems

Konopińska

Pietrzak

Mazur

et al. 2015

Heliyon

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Porphyrins and metalloporphyrins are promising new protein labels that can be detected using multiple techniques; improving the reliability of the analysis and broadening the range of the linear response. Here, we investigate the potential of 5,10,15,20-tetraphenyl-21H,23H-porphyrin (Tpp) as a hybrid protein label. The electrochemical and optical properties of porphyrin conjugated with bovine serum albumin (BSA), chicken egg albumin (CEA) and immunoglobulin G (IgG) were determined and optimal conditions for Tpp-protein conjugation established. Model conjugates of carboxylated Tpp with BSA and short peptides were characterized using differential pulse voltammetry, UV–Vis spectrophotometry and spectrofluorimetry. These results reveal that Tpp is a promising molecule to be used in a triple detection protein labelling system.

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Section: Resultsmentioning

confidence: 99%

Tetraphenylporphyrin as a protein label for triple detection analytical systems

Konopińska

Pietrzak

Mazur

et al. 2015

Heliyon

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“…The exact attribution of the two subsequent reductions of 4H 2 *À at E 2c and E 3c proved more difficult, mainly due to the observation of three reduction waves in the whole accessible potential domain, which stands in sharp contrast with the standard electrochemical signature of porphyrins involving only two successive reductions yielding the anion radical (PH 2 *À ) and dianion (PH 2 2À ) species, respectively. [54][55][56][57][58][59] Such standard signature was for instance observed with the C 6 F 5 -substituted reference compounds 7H 2 , 8H 2 and 9H 2 , which contrasts with the three reduction waves À 1.79 [a] (1e À , na) À 1.522 [a] À 0.984 [b] (1e À , 66)…”

Section: Electrochemical Studiesmentioning

confidence: 99%

Synthesis and Electrochemistry of Free‐Base Porphyrins Bearing Trifluoromethyl meso‐Substituents

et al. 2022

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CF3‐substituted porphyrins have attracted increasing interest over the past decade. However, the number of examples reported in the literature remains quite limited and much remains to be done to understand the properties and reactivity of these molecules. We are now reporting on the synthesis of a series of free base porphyrins incorporating one, two and three CF3 substituents, including the 5,10,15‐tris(CF3) substituted porphyrin which has never been described before. We have also carried out detailed electrochemical and spectroscopic analyses aiming at assessing the electron‐withdrawing properties of the CF3 substituents compared to the widely used C6F5. Our studies led us to propose an interpretation of the quite unusual electrochemical signature of these molecules featuring three successive one‐electron reduction waves.

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“…Therefore, the ligand in this intermediate is reduced simultaneously with the metallic center at −0.31 V differently for what is observed for the protoporphyrin IX, in which the ligand is electrochemically reduced at much negative potential. 29 Consequently, the electrochemical signal corresponding to the reduction of hematin comprises two different electrochemical processes.…”

Section: Electrochemical Behavior Of Htin-gce On Negative Applied Pot...mentioning

confidence: 99%

Insights toward the Electrochemical Behavior of Hematin Using a Hematin Modified Glassy Carbon Electrode

Buoro

Campos

Bacil

et al. 2016

J. Electrochem. Soc.

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The electrochemical behavior of heme-phorphyrin iron (III) centered hematin (Htin) was investigated at a Htin modified glassy carbon electrode with cyclic, differential pulse, square wave voltammetry in different pH values. For all pH values, the electrochemical process attributed to the reduction of hematin follows an EE mechanism, in which the ligand suffers mediated electrochemical reduction by the iron metallic center. At the backward scan, the same mechanism is observed for the oxidation of hematin in pH > 5.5. However, the electrochemical oxidation at backward scan in pH < 5.5 occurs firstly and directly at the ligand with the formation of IS (intermediate specie) that is further oxidized at the metallic center and forms Fe(Htin) 3+ . In acid and neutral media, the oxidation of hematin at the positive potential range is an irreversible and pH-dependent process that follows an ECE mechanism. In the first step, the electrochemical oxidation of hematin involves the transfer of one electron from the pyrrolic nitrogen heteroatom with the formation of a cationic radical that loses its iron (III) center in a subsequent chemical step. The resulting cationic radical suffers further oxidation to produce a structure similar to the protoporphyrin IX.

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The influence of the halide electrolyte on the electrochemical reduction pathway of some meso-tetrasubstituted porphyrin free bases in N,N-dimethyl formamide

Cited by 4 publications

References 22 publications

Tetraphenylporphyrin as a protein label for triple detection analytical systems

Tetraphenylporphyrin as a protein label for triple detection analytical systems

Synthesis and Electrochemistry of Free‐Base Porphyrins Bearing Trifluoromethyl meso‐Substituents

Insights toward the Electrochemical Behavior of Hematin Using a Hematin Modified Glassy Carbon Electrode

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