The voltammetric determination of 4-nitrobiphenyl

1991 ◽  
Vol 56 (3) ◽  
pp. 595-601 ◽  
Author(s):  
Jiří Barek ◽  
Gulamustafa Malik ◽  
Jiří Zima
Keyword(s):  
Differential Pulse Voltammetry ◽  
Differential Pulse ◽  
Voltammetric Determination ◽  
Hanging Mercury Drop Electrode ◽  
Optimum Conditions ◽  
Mercury Drop Electrode ◽  
Working Electrode ◽  
Pulse Voltammetry ◽  
Unstirred Solution

Optimum conditions were found for the determination of 4-nitrobiphenyl by fast scan differential pulse voltammetry at a hanging mercury drop electrode in the concentration range 1 . 10-5 to 2 . 10-7 mol l-1. A further increase in sensitivity was attained by adsorptive accumulation of this substance on the surface of the working electrode, permitting determination in the concentration range (2 – 10) . 10-8 mol l-1 with one minute accumulation of the substance in unstirred solution or (2 – 10) . 10-9 mol l-1 with three-minute accumulation in stirred solution. Linear scan voltammetry can be used to determine 4-nitrobiphenyl in the concentration range (2 – 10) . 10-9 mol l-1 with five-minute accumulation in stirred solution, with the advantage of a smoother baseline and smaller interference from substances that yield only tensametric peaks.

Polarographic and Voltammetric Determination of 1-(2'-Nitrophenyl)-3,3-dimethyltriazene

1993 ◽  
Vol 58 (9) ◽  
pp. 2021-2038 ◽  
Author(s):  
Jiří Barek ◽  
Dana Dřevínková ◽  
Jiří Zima
Keyword(s):  
Differential Pulse Voltammetry ◽  
Differential Pulse ◽  
Differential Pulse Polarography ◽  
Hanging Mercury Drop Electrode ◽  
Optimum Conditions ◽  
Concentration Region ◽  
Mercury Drop Electrode ◽  
Pulse Polarography ◽  
Pulse Voltammetry

The polarographic behaviour of 1-(2'-nitrophenyl)-3,3-dimethyltriazene in mixed aqueous-methanolic solvent was investigated by tast polarography, differential pulse polarography, and fast scan differential pulse voltammetry at a hanging mercury drop electrode. A mechanism is suggested for the reduction of the compound investigated. The optimum conditions were found for the determination of this analyte by tast polarography over the concentration region of 100 to 2 μmol l-1 and by differential pulse polarography or fast scan differential pulse voltammetry at a hanging mercury drop electrode over the region of 100 to 0.2 μmol l-1. Additional sensitivity increase in the last-mentioned technique was achieved by adsorptive accumulation of analyte on the hanging mercury drop surface, owing to which the concentration region was depressed to 0.1 - 0.02 μmol l-1.

Polarographic and voltammetric determination of 6-mercaptopurine and 6-thioguanine

1986 ◽  
Vol 51 (11) ◽  
pp. 2466-2472 ◽  
Author(s):  
Jiří Barek ◽  
Antonín Berka ◽  
Ludmila Dempírová ◽  
Jiří Zima
Keyword(s):  
Detection Limit ◽  
Differential Pulse Voltammetry ◽  
Detection Limits ◽  
Differential Pulse ◽  
Voltammetric Determination ◽  
Differential Pulse Polarography ◽  
Hanging Mercury Drop Electrode ◽  
Pulse Polarography ◽  
Pulse Voltammetry

Conditions were found for the determination of 6-mercaptopurine (I) and 6-thioguanine (II) by TAST polarography, differential pulse polarography and fast-scan differential pulse voltammetry at a hanging mercury drop electrode. The detection limits were 10-6, 8 . 10-8, and 6 . 10-8 mol l-1, respectively. A further lowering of the detection limit to 2 . 10-8 mol l-1 was attained by preliminary accumulation of the determined substances at the surface of a hanging mercury drop.

The Polarographic and Voltammetric Determination of 1(4'-Carbamoylphenyl)-3,3-dimethyltriazene

1992 ◽  
Vol 57 (6) ◽  
pp. 1230-1236
Author(s):  
Jiří Barek ◽  
Viktor Mejstřík ◽  
Saafa Toubar ◽  
Jiří Zima
Keyword(s):  
Differential Pulse ◽  
Differential Pulse Polarography ◽  
Test Substance ◽  
Hanging Mercury Drop Electrode ◽  
Optimum Conditions ◽  
Mercury Drop Electrode ◽  
Polarographic Behaviour ◽  
Pulse Polarography ◽  
Pulse Voltammetry

A study was made of the polarographic behaviour of 1-(4'-carbamoylphenyl)-3,3-dimethyltriazene and optimum conditions were found for its determination by tast polarography and differential pulse polarography at a static mercury drop electrode and by fast scan differential pulse voltammetry at a hanging mercury drop electrode in the concentration range 1 . 10-4 to 2 . 10-7 mol l-1. A further increase in the sensitivity can be achieved through adsorptive accumulation of the test substance on the surface of a hanging mercury drop, permitting the determination to be extended to the concentration range 1 . 10-7 - 2 . 10-9 mol l-1.

The polarographic and voltammetric determination of 2-amino-5-sulphoamoylnaphthalene-azo-(2’-chloro-4’-nitrobenzene)

1988 ◽  
Vol 53 (1) ◽  
pp. 19-33 ◽  
Author(s):  
Jiří Barek ◽  
Jana Balsiene ◽  
Antonín Berka ◽  
Ivana Hauserová ◽  
Jiří Zima
Keyword(s):  
Detection Limit ◽  
Differential Pulse Voltammetry ◽  
Differential Pulse ◽  
Linear Potential ◽  
Polarographic Reduction ◽  
Hanging Mercury Drop Electrode ◽  
Mercury Drop Electrode ◽  
Pulse Voltammetry ◽  
Layer Chromatography

The polarographic reduction of the title azo dye was studied, a mechanism was suggested and optimal conditions were determined for analytical utilization of this process. A detection limit of 3 . 10-7 mol 1-1 was obtained using fast scan differential pulse voltammetry and 0.7 . 10-7 mol 1-1 using linear potential scan voltammetry at a hanging mercury drop electrode. The detection limit can be decreased by adsorptive accumulation of the determined substance on the surface of the hanging mercury drop electrode, to 1 . 10-8 mol 1-1 for fast scan differential pulse voltammetry and 0.6 . 10-8 mol 1-1 for linear scan voltammetry. The selectivity of the determination can be improved by preliminary separation by extraction or thin-layer chromatography.

The polarographic and voltammetric determination of semitrypane blue

1989 ◽  
Vol 54 (6) ◽  
pp. 1538-1548
Author(s):  
Jiří Barek ◽  
Ashutosh Ghosh ◽  
Jiří Zima
Keyword(s):  
Differential Pulse Voltammetry ◽  
Mercury Electrode ◽  
Differential Pulse ◽  
Differential Pulse Polarography ◽  
Polarographic Reduction ◽  
Hanging Mercury Drop Electrode ◽  
Mercury Drop Electrode ◽  
Dropping Mercury Electrode ◽  
Pulse Voltammetry

The polarographic reduction of the azodye semitrypane blue has been studied, a mechanism has been proposed and optimal conditions have been found for the determination of this substance by TAST polarography (to 2.10-6 mol l-1) and differential pulse polarography (to 1.10-7 mol l-1) at a classical dropping mercury electrode and by fast scan differential pulse voltammetry (to 1.10-8 mol l-1) and linear scan voltammetry (to 1.10-8 mol l-1) at a hanging mercury drop electrode. The detection limit was decreased to 1.10-9 mol l-1 for fast scan differential pulse voltammetry and 1.10-10 mol l-1 for linear scan voltammetry by using adsorptive accumulation of the determined substance at the hanging mercury drop electrode.

Polarographic and voltammetric determination of 1-(2’-carbamoylphenyl)-3,3-dimethyltriazene

1991 ◽  
Vol 56 (10) ◽  
pp. 2073-2081 ◽  
Author(s):  
Jiří Barek ◽  
Safa Toubar ◽  
Jiří Zima
Keyword(s):  
Differential Pulse ◽  
Differential Pulse Polarography ◽  
Test Substance ◽  
Hanging Mercury Drop Electrode ◽  
Optimum Conditions ◽  
Mercury Drop Electrode ◽  
Polarographic Behaviour ◽  
Pulse Polarography ◽  
Pulse Voltammetry

A study was carried out of the polarographic behaviour of the genotoxic substance 1-(2’-carbamoylphenyl)-3,3-dimethyltriazene and optimum conditions were found for its determination by tast polarography or differential pulse polarography at a static mercury drop electrode and by fast scan differential pulse voltammetry at a hanging mercury drop electrode in the concentration range 1 . 10-4 -2 . 10-7 mol 1-1. The sensivity of the determination can be further improved through adsorptive accumulation of the test substance on the surface of the hanging mercury drop electrode; five-minute accumulation in unstirred solution permits determination in the concentration range (2-10 . 10-8 mol 1-1 and two-minute accumulation in stirred solution allows determination in the range (2-10) . 10-9 mol 1-1.

The determination of 4-substituted derivatives of N-nitroso-N-methyl aniline by fast scan differential pulse voltammetry at a hanging mercury drop electrode

1991 ◽  
Vol 56 (12) ◽  
pp. 2815-2826 ◽  
Author(s):  
Jiří Barek ◽  
Viktor Mejstřík ◽  
Ivana Švagrová ◽  
Jiří Zima
Keyword(s):  
Differential Pulse Voltammetry ◽  
Differential Pulse ◽  
Test Sample ◽  
Nitroso Compounds ◽  
Hanging Mercury Drop Electrode ◽  
Mercury Drop Electrode ◽  
Pulse Voltammetry ◽  
Layer Chromatography ◽  
Derivatives Of

Optimum conditions were found for the determination of N-nitroso-N-methyl aniline and its derivatives substituted in the 4 position by -CH3, -OCH3, -Cl, -CN, -OH or -NO2 groups by fast scan differential pulse voltammetry at a hanging mercury drop electrode in the concentration range 1 10-5-2 10-7 mol l-1. It was demonstrated that these techniques are useful for the analysis of a mixture of the test substances either directly or after separation by thin-layer chromatography and that false positive results can be eliminated by UV irradiation of the test sample. An attempt to further increase the sensitivity by adsorptive accumulation of the test substances on the surface of the hanging mercury drop electrode was not successful as the test N-nitroso compounds are practically not adsorbed on this electrode.

scholarly journals Determination of methiocarb pesticide using differential pulse voltammetry with a boron-doped diamond electrode

2015 ◽  
Vol 7 (11) ◽  
pp. 4671-4677 ◽  
Author(s):  
J. Chýlková ◽  
M. Tomášková ◽  
I. Švancara ◽  
L. Janíková ◽  
R. Šelešovská
Keyword(s):  
Differential Pulse Voltammetry ◽  
Rapid Method ◽  
Differential Pulse ◽  
Voltammetric Determination ◽  
Boron Doped Diamond ◽  
Diamond Electrode ◽  
Boron Doped ◽  
Boron Doped Diamond Electrode ◽  
Pulse Voltammetry

In this article, a simple and rapid method is described for voltammetric determination of methiocarb (MTC, a pesticide of the carbamate type).

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