Isotachophoresis and isotachophoresis — zone electrophoresis separations of inorganic anions present in water samples on a planar chip with column-coupling separation channels and conductivity detection

Bodor, Róbert; Madajová, V.; Kaniansky, Dušan; Masár, Marián; Jöhnck, Matthias; Stanislawski, Bernd

doi:10.1016/s0021-9673(00)01080-3

Cited by 105 publications

(97 citation statements)

References 32 publications

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“…Compared with traditional methods the technique present as advantages: small sample volume, high efficiency and precision, short analysis time and often without any pretreatment of the sample before injection. However, the CE methodologies described in the literature applied to nitrate and nitrate analysis in fishery wastewater and river water was required pretreatment as centrifugation and filtration to remove particulates and colloids [17,18]. In addition we not found reports in the literature involving analysis of nitrite and nitrate in urban stream by CE.…”

Section: Introductionmentioning

confidence: 82%

Optimization of an Alternative Methodology for Simultaneous Analysis of Nitrite and Nitrate in Water from Urban Stream by Capillary Electrophoresis under Direct UV Detection

de¹,

Carmo²,

Soares³

et al. 2012

AJAC

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An alternative methodology for simultaneous determination of nitrite and nitrate by capillary zone electrophoresis using direct detection UV at 210 nm under reverse electrosmotic flow is proposed. The optimization of the electrolyte composition took into account: the buffer and solutes mobilities; the low absorbance of the buffer at 210 nm; the high baseline stability and the short analysis time. The optimized background electrolyte consisted of 100 mmol·L -1 TRIS/HCl buffer and 0.15 mmol·L -1 CTAB at pH 8.2. The proposed method was successfully applied in the analysis of nitrite and nitrate in urban stream samples without usual pretreatment.

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Section: Introductionmentioning

confidence: 82%

Optimization of an Alternative Methodology for Simultaneous Analysis of Nitrite and Nitrate in Water from Urban Stream by Capillary Electrophoresis under Direct UV Detection

de¹,

Carmo²,

Soares³

et al. 2012

AJAC

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“…(14) are calculated using ionic strength at each time step to compute the mixed equilibrium constants in Eqs. (12) and (13). Finally, the ionic-strengthdependent effective mobility, m i h i, of each ampholyte is computed from Eq.…”

Section: Computational Model and Assumptionsmentioning

confidence: 99%

“…These include IEF [1][2][3][4], ITP [5][6][7], ZE [8][9] and CE [10]. Recently, multi-dimensional separation techniques such as IEF-ZE [11], IEF-CE [12], ITP-ZE [13] and ITP-IEF [14] have been reported in microchip to enhance separation efficiency of large numbers of proteins. As 2-D separation techniques are integrated onto small microchips, one has to design appropriate channel configurations using complex geometries such as cross-channels, T-channels, dog-leg or horseshoe channels in order to obtain high-resolution separations.…”

Section: Introductionmentioning

confidence: 99%

Dispersion of protein bands in a horseshoe microchannel during IEF

2009

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Ampholyte-based IEF is simulated for a 2-D horseshoe microchannel. The IEF model takes into account ionic-strength-dependent mobility corrections for both proteins and ampholytes. The Debye-Huckel-Henry model is employed to correct the protein mobilities and the Onsager-Debye-Huckel model is used to obtain effective mobilities of ampholytes from their limiting mobility. IEF simulations are conducted in the presence of 25 ampholytes (DeltapK=3.0) within a pH range of 6-9 under an electric field of 300 V/cm and using four proteins (pIs=6.49, 7.1, 7.93 and 8.6) focused in a 1-cm-long microchannel. The numerical results show that the concentrations of proteins and ampholytes are different when mobility corrections are considered but that the focusing positions remain the same regardless of mobility corrections. Our results also demonstrate that, unlike linear electrophoresis in which the bands deform significantly as they traverse a bend, during the transient portion of IEF racecourse dispersion is mitigated by focusing and, at focused-state, those bands that focus in the bend show no radial concentration dependence, i.e. they completely recover from racecourse dispersion, even within a tight turn.

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“…The most common techniques for fluoride assay are potentiometry using a fluorideselective electrode (ISE) [3][4][5] and ion chromatography (IC). 6 Several other techniques have been reported for the determination of fluoride in drinking water, such as capillary electrophoresis, 7 solvent-extraction coupled to fluorometry. [8][9][10] There are a few spectrophotometric reports in the literature based on a decolorizing effect of fluoride on a colored metal-dye complex.…”

Section: Introductionmentioning

confidence: 99%

Spectrophotometric Determination of Trace Amounts of Fluoride Using an Al-Xylenol Orange Complex as a Colored Reagent

et al. 2009

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A new spectrophotometric reagent for the determination of trace amounts of fluoride has been introduced. This method is based on the decolorization of a complex of Al(III) with xylenol orange (XO) as an ultra-sensitive colored reagent. Since the Al-XO complex plays an important role in this method, the protonation and complexation of XO with Al(III) at an ionic strength of 0.1 mol L -1 at 25 C has been studied by a spectrophotometric global analysis method. The EQUISPEC program was used to evaluate the protonation constants of XO and the stability constants of the formed complexes with Al(III). The protonation and the stability constants of the major complex species such as ML, MLH and MLH2, were determined. Finally, a spectrophotometric method for the assay of fluoride based on a decrease of the color intensity of the Al-XO complex, in an aqueous solution has been designed. The effects of some important variables on the determination of fluoride based on the proposed method were investigated. The method was applied to the determination of fluoride under the optimum conditions (pH 5.2, ionic strength 0.1 mol L -1 , 25 C). The determination of fluoride in the range of 0.08 -1.4 μg mL -1 (SD = 1.2%) was successfully performed. Interferences of Fe(III) were easily eliminated by using ascorbic acid. The proposed method was applied to the determination of trace amounts of fluoride content of some real water samples.

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Isotachophoresis and isotachophoresis — zone electrophoresis separations of inorganic anions present in water samples on a planar chip with column-coupling separation channels and conductivity detection

Cited by 105 publications

References 32 publications

Optimization of an Alternative Methodology for Simultaneous Analysis of Nitrite and Nitrate in Water from Urban Stream by Capillary Electrophoresis under Direct UV Detection

Optimization of an Alternative Methodology for Simultaneous Analysis of Nitrite and Nitrate in Water from Urban Stream by Capillary Electrophoresis under Direct UV Detection

Dispersion of protein bands in a horseshoe microchannel during IEF

Spectrophotometric Determination of Trace Amounts of Fluoride Using an Al-Xylenol Orange Complex as a Colored Reagent

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