Detection of Cu, Pb, Cd and Zn in Mexican Spirituous Beverages by Differential Pulse Polarography (DPP)

A method is described for determining total platinum content in urine, blood plasma and tissues of patients or experimental animals receiving cis-dichlorodiamineplatinum(II). The method is based on drying and combustion of the biological material in a muffle furnace. The product of the combustion is dissolved successively in aqua regia, hydrochloric acid and ethylenediamine. The resulting platinum-ethylenediamine complex yields a catalytic current at a dropping mercury electrode allowing to determine platinum by differential pulse polarography. Platinum levels of c. 50-1 000 ng per ml of the biological fluid or per 0.5 g of a tissue can readily be analyzed with a linear calibration.

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Polarography of N,N-dimethyl-4-amino-4'-hydroxyazobenzene in water-methanol mixtures

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19850712 ◽

1985 ◽

Vol 50 (3) ◽

pp. 712-725 ◽

Cited By ~ 2

Author(s):

Jiří Barek ◽

Lubomír Kelnar

Keyword(s):

Differential Pulse ◽

Differential Pulse Polarography ◽

Polarographic Reduction ◽

Reduction Mechanism ◽

Pulse Polarography ◽

Methanol Medium

The polarographic reduction of N,N-dimethyl-4-amino-4'-hydroxyazobenzene in water-methanol medium was investigated. Evidence is presented for adsorption of the depolarizer on the electrode, and a reduction mechanism is proposed. Conditions are indicated for the determination of this compound in the concentration range 10-4-10-6 mol/l by d.c. polarography, 10-5 to 3 . 10-7 mol/l by Tast polarography, and 10-5-3 . 10-8 mol/l by differential pulse polarography.

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

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19862466 ◽

1986 ◽

Vol 51 (11) ◽

pp. 2466-2472 ◽

Cited By ~ 9

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.

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The polarographic and voltammetric determination of 2,6-dicyano-4-nitro-2'-acetylamino-4'-diethylaminoazobenzene

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19901508 ◽

1990 ◽

Vol 55 (6) ◽

pp. 1508-1517 ◽

Cited By ~ 1

Author(s):

Jiří Barek ◽

Dagmar Civišová ◽

Ashutosh Ghosh ◽

Jiří Zima

Keyword(s):

Azo Dye ◽

Differential Pulse ◽

Differential Pulse Polarography ◽

Determination Limit ◽

Polarographic Reduction ◽

Hanging Mercury Drop Electrode ◽

Optimal Conditions ◽

Pulse Polarography ◽

Pulse Voltammetry

The polarographic reduction of the title azo dye was studied and optimal conditions were found for its analytical utilization in the concentration range 1 . 10-6 - 1 . 10-7 mol l-1 using differential pulse polarography and 1 . 10-6 - 1 . 10-8 mol l-1 using fast scan differential pulse voltammetry or linear scan voltammetry at a hanging mercury drop electrode. When the latter technique is combined with adsorptive accumulation of the studied substance on the surface of the hanging mercury drop, the determination limit can be further decreased to 3 . 10-9 mol l-1.

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Polarographic and voltammetric determination of N,N’-dinitrosopiperazine

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19911434 ◽

1991 ◽

Vol 56 (7) ◽

pp. 1434-1445 ◽

Cited By ~ 1

Author(s):

Jiří Barek ◽

Ivana Švagrová ◽

Jiří Zima

Keyword(s):

Mercury Electrode ◽

Linear Sweep Voltammetry ◽

Differential Pulse ◽

Differential Pulse Polarography ◽

Polarographic Reduction ◽

Concentration Region ◽

Pulse Polarography ◽

Chemical Efficiency ◽

Dropping Mercury Electrode

Polarographic reduction of the genotoxic N,N’-dinitrosopiperazine was studied and its mechanism was suggested. Optimum conditions were established for the determination of this substance by tast polarography over the concentration region of 1 . 10-3 to 1 . 10-6 mol l-1 and by differential pulse polarography on the conventional dropping mercury electrode or by fast scan differential pulse voltammetry and linear sweep voltammetry on a hanging mercury drop electrode over the concentration region of 1 . 10-3 to 1 . 10-7 mol l-1. Attempts at increasing further the sensitivity via adsorptive accumulation of the analyte on the surface of the hanging mercury drop failed. The methods are applicable to the testing of the chemical efficiency of destruction of the title chemical carcinogen based on its oxidation with potassium permanganate in acid solution.

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Determination of Organic Bases by Ion-Pair Extraction Polarography Using Orange II as Counter Ion

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19922272 ◽

1992 ◽

Vol 57 (11) ◽

pp. 2272-2278 ◽

Cited By ~ 2

Author(s):

Václav Koula ◽

Daria Kučová ◽

Jiří Gasparič

Keyword(s):

Model Compound ◽

Differential Pulse ◽

Ion Pair ◽

Differential Pulse Polarography ◽

Orange Ii ◽

Organic Bases ◽

Counter Ion ◽

Pulse Polarography ◽

Ammonium Compounds

The combination of ion-pair extraction and differential pulse polarography is shown to be a method suitable for the determination of 10-7 mol l-1 concentrations of organic bases of quaternary ammonium compounds. Orange II (4-[2-hydroxy-1-naphtyl]azobenzenesulfonic acid) was found to be an appropriate polarographically active counter-ion. The proposed method was used for the determination of tetrapentylammonium bromide (as model compound), Septonex ([1-(ethoxycarbonyl)-pentadecyl]trimethylammonium bromide) and codeine.

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Polarographic Determination of 6-β-D-Glucopyranosyloxy-7-hydroxycoumarin

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19960333 ◽

1996 ◽

Vol 61 (3) ◽

pp. 333-341

Author(s):

Jiří Barek ◽

Roman Hrnčíř ◽

Josino C. Moreira ◽

Jiří Zima

Keyword(s):

Natural Compound ◽

Mercury Electrode ◽

Direct Determination ◽

Differential Pulse ◽

Differential Pulse Polarography ◽

Whitening Agent ◽

Polarographic Behaviour ◽

Pulse Polarography ◽

Dropping Mercury Electrode

The polarographic behaviour was studied for 6-β-D-glucopyranosyloxy-7-hydroxycoumarin, a natural compound serving as an optical whitening agent. The substance can be quantitated by tast polarography, differential pulse polarography using a conventional dropping mercury electrode, and differential pulse polarography using a static mercury drop electrode over the regions of 20-1 000, 2-1 000, and 0.2-1 000 μmol l-1, respectively. The methods developed for the quantitation of the compound were applied to its direct determination in a raw product.

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Polarographic and Voltammetric Determination of Trace Amounts of 3-Nitrofluoranthene

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20061571 ◽

2006 ◽

Vol 71 (11-12) ◽

pp. 1571-1587 ◽

Cited By ~ 6

Author(s):

Karel Čížek ◽

Jiří Barek ◽

Jiří Zima

Keyword(s):

River Water ◽

Solid Phase ◽

Mercury Electrode ◽

Stripping Voltammetry ◽

Differential Pulse ◽

Differential Pulse Polarography ◽

Pulse Polarography ◽

Dropping Mercury Electrode ◽

Separation And Preconcentration

The polarographic behavior of 3-nitrofluoranthene was investigated by DC tast polarography (DCTP) and differential pulse polarography (DPP), both at a dropping mercury electrode, differential pulse voltammetry (DPV) and adsorptive stripping voltammetry (AdSV), both at a hanging mercury drop electrode. Optimum conditions have been found for its determination by the given methods in the concentration ranges of 1 × 10-6-1 × 10-4 mol l-1 (DCTP), 1 × 10-7-1 × 10-4 mol l-1 (DPP), 1 × 10-8-1 × 10-6 mol l-1 (DPV) and 1 × 10-9-1 × 10-7 mol l-1 (AdSV), respectively. Practical applicability of these techniques was demonstrated on the determination of 3-nitrofluoranthene in drinking and river water after its preliminary separation and preconcentration using liquid-liquid and solid phase extraction with the limits of determination 4 × 10-10 mol l-1 (drinking water) and 2 × 10-9 mol l-1 (river water).

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