Showing papers on "Polarography published in 1988"
TL;DR: In adsorptive transfer stripping voltammetry (AdTSV), DNA is first adsorbed at the electrode, the electrode is washed and transferred in the medium not containing DNA, and voltammetric analysis is performed in this medium, which makes it possible to reduce the volume of the analyzed sample by two orders of magnitude as compared to that of conventionalvoltammetry.
148 citations
TL;DR: In this paper, the reduction process of (FeSCNNO)+ with dropping Mercury Electrode (DME) has been studied by linear sweep polarography (LSP), dc polarography, cyclic voltammetry, and controlled potential coulometry and the detection limit is 1 × 10−8M (0.46 ppb NO2−).
59 citations
TL;DR: In this paper, the transfer of carboxylate, RCOO−, and sulphonate, RSO3−, anions was investigated at the aqueous/1,2-dichloroethane or nitrobenzene interface, based on the half-wave potentials, ΔV12s, of the polarograms which can be related to the transfer energies, δgtrs.
48 citations
TL;DR: A differential pulse polarographic method, using the dropping mercury electrode for the determination of the herbicides atrazine, prometrine and simazine is described, with a view to its use for electrochemical detection of the Herbicides after their separation by HPLC.
40 citations
TL;DR: In this article, it was shown that upon integrating the current following the polarizing pulse immediately after the capacitive contribution has faded out (which requires a time tmin = 3-5 ms in aqueous solutions) up to the end of the pulse, the signal to noise ratio is increased by 1-2 orders of magnitude with respect to conventional NPP at a static electrode.
26 citations
TL;DR: In this paper, the authors presented a method of measuring simultaneously oxygen diffusion coefficients and solubilities in aqueous electrolyte solutions with a membrane-covered oxygen electrode, and the experimental results on oxygen diffusion coefficient and Solubilities showed an excellent accord with the literature data.
25 citations
TL;DR: In this article, a linear sweep polarographic wave appears at −042 V (vs SCE) in anodic sweeps, the derivative peak current is directly proportional to the concentration of thiocyanate.
24 citations
TL;DR: In this article, the electron transfer reaction of Desulfovibrio vulgaris Hildenborough cytochrome c 3 at the mercury and the pyrolytic graphite electrode was investigated using differential pulse and cyclic voltammetry at various pH.
23 citations
TL;DR: A new method is described for the microdetermination of Mo(VI) in natural waters and sea-water by differential-pulse polarography based on the catalytic wave caused by Mo( VI) in nitrate medium following preconcentration by co-flotation on Fe(III) hydroxide.
20 citations
19 citations
TL;DR: In this article, N-Methylnicotinamide (MNA) was studied by dc and DP polarography and linear sweep cyclic voltammetry in acidic media (pH < 3).
TL;DR: In this article, 18 uracil derivatives were studied by d.c.p. polarography, differential-pulse (d.p.)polarography and d. p. cathodic stripping voltammetry, and the shapes, heights and potentials of the peaks depended on the kind and position of the substituent on the pyrimidine ring.
TL;DR: The application of a laboratory-built sessile mercury drop detector in drug analysis has been illustrated by the flow injection amperometric determination of nitrofurantoin and acetazolamide.
Abstract: The application of a laboratory-built sessile mercury drop detector in drug analysis has been illustrated by the flow injection amperometric determination of nitrofurantoin and acetazolamide. Nitrofurantoin was determined in the range 1–50 µg ml–1 at –0.70 V vs. SCE in a carrier stream consisting of pH 7.5 Britton-Robinson buffer containing sulphite to lower the background oxygen level; acetazolamide was determined in the range 10–70 µg ml–1 at –0.85 V vs. SCE in 0.1 M hydrochloric acid. The procedures were applied with good accuracy and precision to the determination of the drugs in tablet formulations.
TL;DR: In this paper, the underpotential deposition of Hg on polycrystalline Au was investigated by potentiostatic step measurements at the rotating ring disk electrode in perchloric acid solutions of hg(I) and Hg(II) and the analysis of the current transients according to the procedure given in Part I demonstrates that the deposit consists of adsorbed Hg with a partial charge 1-l = 053 and of completely discharged mercury Hg (0)
TL;DR: In this paper, the authors applied square-wave voltammetry, ac polarography and radio-frequency polarography to the system of moldm3 Bi(III) in (1-x) moldm 3 HClO4 + xmoldm3 HClCl enhancement of the SW peak currents.
TL;DR: An electroanalytical study based on dc and differential pulse polarography (DPP) and coulometry is described for Guthion, S -(3,4-dihydro-4-oxobenzo[d]-(1,2,3)-triazin-3-yl-methyl)- O, O -dimethylphos-phorodithioate, in 20% (v/v) MeOH/H 2 O, Britton-Robinson buffer, pH 4.3 as mentioned in this paper.
TL;DR: Isonicotinic amide was studied by dc and DP polarography and linear sweep cyclic voltammetry in a strong acid medium (pH) as discussed by the authors, where the process occurs through the formation of a protonated gem-hydroxylamine which is transformed into the aldehyde via a substitution by water, which is the rate determining step.
TL;DR: The electrochemical behaviour of cefsulodin in buffered aqueous solutions using differential-pulse polarography, direct-current polarography and cyclic voltammetry finds the main wave observed is attributed to the reduction of the isonicotinamide substituent.
Abstract: A study has been carried out on the electrochemical behaviour of cefsulodin in buffered aqueous solutions using differential-pulse polarography (DPP), direct-current polarography (DCP) and cyclic voltammetry. Both the DPP and DCP techniques allow the determination of this antibiotic in the concentration range 1–200 p.p.m. The main wave observed is attributed to the reduction of the isonicotinamide substituent. The electrochemical behaviour has been found to change at a concentration of about 60 p.p.m.
TL;DR: In this article, an approximate equation for differential pulse polarography applicable to an electrodimerization process is tested with the reduction of N-methylnicotinamide, and the variation of Ep with the reactant concentration is derived and tested.
TL;DR: In this paper, direct current and differential pulse polarization, linear sweep cyclic voltammetry, UV and fluorescence spectroscopy techniques were employed to study the reduction of 2-hydroxy-3-phenyl-6-methylpyrazine (HPMP), a degradation product of β-lactam antibiotics.
TL;DR: In this article, the electrochemical properties of two electrophores (bipyridine and N-oxide functions) are found to be electroreducible in an aqueous Britton-Robinson buffer.
TL;DR: In this paper, a single sweep polarographic method for the determination of trace amounts of palladium has been developed, which is attributed to the reduction of Pd(II) in the complex to palladium amalgam.
TL;DR: In this paper, the anodic processes at the mercury electrode in 2-mercaptoethanol solutions are studied by various polarographic techniques (d.c., a.c. and differential pulse), controlled-potential coulometry, cyclic voltammetry and differential capacity curves.
TL;DR: The determination of total aluminum in water by furnace atomic absorption spectrometry is best performed with a prior sample treatment with 1% HNO3 + 2% H2O2 or Acid Alizarin Violet N: detection limits of a few μgL−1 are reliably obtained.
Abstract: The determination of total aluminum in water by furnace atomic absorption spectrometry is best performed with a prior sample treatment with 1% HNO3 + 2% H2O2 or Acid Alizarin Violet N: detection limits of a few μgL−1 are reliably obtained. Ionic aluminum may be measured at levels down to 25 μgL−1 by differential pulse polarography of the aluminum complex with Acid Alizarin Violet N; excesses of Fe3+, Cl−, and EDTA interfere.
TL;DR: In this article, a method for the determination of cobalt in zinc plant solutions was proposed, which can be used for determining cobalt(II) in the presence of a 50 000-fold excess of zinc by differential pulse polarography.
Abstract: Cobalt(II) can be determined in 0.1 mol/l Na3citrate + 0.1 mol/l NH4Cl + 0.08% dimethylglyoxime as supporting electrolyte in the presence of a 50 000-fold excess of zinc by differential pulse polarography. The limit of determination is 4.2×10−5 mol/l Co (2.5 mg/l). Linear calibration curves are obtained within the range of 1×10−7 to 5×10−6 mol/l cobalt without zinc and in the presence of 5×10−3 mol/l Zn. The analytical method developed is suitable for the determination of cobalt in zinc plant solutions.
TL;DR: In this paper, a method for the determination of μgl−1 levels of chlorite by using differential pulse polarography was reported, and the current under these conditions is diffusion-controlled and is a linear function of the chlorite concentration ranging from 2.77 × 10−7 to 2.80×10−4 M (19 μgl −1 to 19 mg l−1).
TL;DR: In this paper, the authors determined theoretical relations between limiting currents and kinetic and thermodynamic parameters for complex systems which require consideration of the fact that the different electrochemical species are influenced by more than one chemical equilibrium.
TL;DR: In this paper, the authors derived an equation for a slow charge transfer reaction in normal pulse polarography (NPP), reverse pulse polarization (RPP), DNPP, and differential pulse polarisation (DPP), which takes into account the cases where the reduction product dissolves both in the electrolyte solution and in the electrode.
TL;DR: Simultaneous determination of Cd(2+), In(3+), and Tl(+) (for which the differences between the stripping peak potentials are 58 and 50 mV, respectively) which is impossible for normal CPSA, voltammetry or differential pulse polarography, has become possible with RD-CCSA.
TL;DR: Etude des courbes polarographiques sur une electrode a goutte de mercure dans des solutions d'acide sulfurique and des ions bromates as mentioned in this paper.
Abstract: Etude des courbes polarographiques sur une electrode a goutte de mercure dans des solutions d'acide sulfurique et des ions bromates