Kinetic spectrophotometric determination of V(IV) in the presence of V(V) by the H-point standard addition method

Safavi, Afsaneh; Abdollahi, Hamid; Sedaghatpour, F; Zeinali, Sedigheh

doi:10.1016/s0003-2670(99)00868-5

Cited by 44 publications

(15 citation statements)

References 19 publications

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“…[52][53][54][55][56][57] Principle component analysis for selection of variables in the application of HPSAM and generalized HPSAM (GHPSAM) was developed. 58 The applications of HPSAM were reported for simultaneous determination of Ca and Mg, 59 iron and vanadium, 60 Cr and Fe, 61 Fe(II) and Fe(III), 62,63 Au and Pd, 64 Fe(III) and V(V), 65 Cr and Co, 66 and V(IV) in the presence of V(V) 67 metal ions. Moreover, HPSAM and GHPSAM were utilized in the determination of cephalexin 68 and simultaneous determination of a binary mixture of anhydrous caffeine and phenazone as well as mixtures of atovaquone and proguanil hydrochloride, 69 theophylline and paraxanthine, 70 amphetamine and methamphetamine, 71 hydrazine and phenylhydrazine, 72 semicarbazide and hydrazine, 73 and periodate-bromate and iodate-bromate mixtures.…”

Section: 51mentioning

confidence: 99%

Recent Developments of Derivative Spectrophotometry and Their Analytical Applications

El‐Sayed

El-Salem

2005

ANAL. SCI.

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The zero-crossing derivative spectra method is the most common procedure for the simultaneous determination of binary mixtures of their overlapping spectra. As an example, the derivative spectra of binary mixtures of phospho-and silicomolybdenum blue are illustrated in Fig. 1. 23 By measuring the derivative values (heights h1 in Fig. 1) for mixtures of phosphate and silicate at 806 nm (zero-crossing wavelength of silicomolybdate complex), one can avoid the interference by silicate and the phosphate concentration can be determined. By measuring the derivative values (heights h2 in Fig. 1 Moreover, one disadvantage of the zero-crossing method is the necessity of selecting critical wavelengths for the measurements. This selection causes considerable loss of sensitivity and precision in case of binary mixtures. The so-called "ratio spectra derivative" permits the use of the wavelengths corresponding to maximum or minimum and also the use of the distance between consecutive maximum and minimum, thus avoiding these problems. 24 Salinas et al. 25 developed a derivative quotient spectra method with a standard divisor when the spectra of the components are overlapped. The method was based on dividing the spectrum for a mixture into the standard spectra for each of the analyses and driving the quotient to obtain a spectrum that is independent of the analyte concentration used as a divisor. The use of standardized spectra as divisors minimizes experimental errors and background noise. 26 An accurate choice of standard divisors and working wavelengths is fundamental for several reasons. 25,27,28 Easy measurements on separate peaks, higher values of the analytical signals and no need to work only at zero-crossing points (sometimes co-existing compounds have no maximum or minimum at these wavelengths) are advantages for ratio spectra derivative spectrophotometry in comparison with the zerocrossing derivative spectrophotometry. Also, the presence of a lot of maxima and minima in ratio spectra derivative data was another advantage, since these wavelengths give an opportunity for the determination of these compounds in the presence of other active compounds and excipients that possibly interfered with the assay. 29 2·1 Resolution of binary and ternary mixtures by applyingderivative ratio spectra (derivative quotient spectra) The absorption spectrum of a mixture of three compounds; A, B and C is determined by this equation:AM,λ i = εA,λ i CA + εB,λ i CB + εC,λ i CC (path-length is 1 cm)where, AM,λ i is the absorbance value of the mixture at wavelength λi, εA,λ i , εB,λ i and εC,λ i are the molar absorptivities of A, B and C at λi, CA, CP and CC are the molar concentrations of A, B and C, respectively. When we divide this spectrum by the spectrum of a standard solution of one of the components (e.g., A of concentration CA). That is bywe obtainThe first derivative of this spectrum ratio givesIf CC = 0, we have the binary mixture of A and B, and the spectrum in this case is:In Eq. (5) we can see that the derivative ratio spectrum of...

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Section: 51mentioning

confidence: 99%

Recent Developments of Derivative Spectrophotometry and Their Analytical Applications

El‐Sayed

El-Salem

2005

ANAL. SCI.

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“…Thus, although HPSAM cannot be used for catalytic-based reactions, it can be used for the simultaneous analysis of binary mixtures in their first order, or pseudo first order, competition reactions. Table 1 presents the application of HPSAM for simultaneous kinetic analysis published during the years 2000-2007 [59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75].…”

Section: H-point Standard Addition Methodsmentioning

confidence: 99%

Recent applications of kinetic methods in multi-component analysis

Bahram

Afkhami

2008

JICS

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This review on multi-component kinetic-based determinations covers most publications in this field during the period 2000-2007. The methodologies applied during recent years have been based on differential reaction rates for simultaneous multicomponent analysis. The literature shows a great attempt to apply chemometric methods, such as partial least squares regression, artificial neural networks, H-point standard addition and a new method involving mean centering of ratio spectra in this field. This review also describes some applications of advanced multiway analysis such as PARAFAC and NPLS from 2000 in the multicomponent kinetic analysis.

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“…V(IV) is less toxic than V(V) in environmental systems and can be produced by various industrial redox processes. It was observed that V(IV) in aqueous solutions forms complexes, most easily with reagents containing oxygen or sulfur donor ligands [3][4][5]. This point testifies to the interest in the determination …”

Section: Introductionmentioning

confidence: 99%

A novel indicator reaction for the catalytic determination of V(V) at ppb levels by the kinetic spectrophotometric method

Ulusoy

Gürkan

2009

Eclet. Quím.

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Abstract:A novel sensitive and relatively selective kinetic method is presented for the determination of V(V), based on its catalytic effect on the oxidation reaction of Ponceau Xylydine by potassium bromate in presence of 5-sulfosalicylic acid (SSA) as activator. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of Ponceau Xylydine at 640 nm between 0.5 to 7 min (the fixed time method) in H 3 PO 4 medium at 25 o C. The effect of various parameters such as concentrations of H 3 PO 4 , SSA, bromate and Ponceau Xylydine, temperature and ionic strength on the rate of net reaction were studied. The method is free from most interferences, especially from large amounts of V(IV). The decrease in absorbance is proportional to the concentration of V(V) over the entire concentration range tested (1-15 ng mL −1 ) with a detection limit of 0.46 ng mL -1 (according to statistical 3S blank /k criterion) and a coefficient of variation (CV) of 1.8% (for ten replicate measurement at 95% confidence level). The proposed method suffers few interferences such as Cr(VI) and Hg(II) ions. The method was successfully applied to the determination of V(V) in tap water, drinking water, bottled mineral water samples and a certified standard reference material such as SRM-1640 with satisfactory results. The vanadium contents of water samples were also determined by FAAS for a comparison. The recovery of spiked vanadium(V) was found to be quantitative and the reproducibility was satisfactory. It was observed that the results of the SRM 1640 were in good agreement with the certified value.

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Kinetic spectrophotometric determination of V(IV) in the presence of V(V) by the H-point standard addition method

Cited by 44 publications

References 19 publications

Recent Developments of Derivative Spectrophotometry and Their Analytical Applications

Recent Developments of Derivative Spectrophotometry and Their Analytical Applications

Recent applications of kinetic methods in multi-component analysis

A novel indicator reaction for the catalytic determination of V(V) at ppb levels by the kinetic spectrophotometric method

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