Ion chromatography exclusion

The ion-exchange resin acts as a semipermeable membrane between the two aqueous phases, (2) and (3). Ionized sample solutes are excluded from the interior water (2) and pass quickly through the column. Nonionic materials are not excluded and they partition between the two water phases, (2) and (3). Thus, they pass more slowly through the column. Nonionic solutes differ in their degree of retardation by the resin phase because of (i) differing polar attraction between the solute and resin functional groups, (ii) differing van der Waals forces between the solutes and the hydrocarbon portion of the resin. 

Ion Chromcitogrciphy, 4th Ei. James S. Fritz and Douglas T. Gjerde Copyright 2009 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 978-3-527-32052-3 

Members of a homologous series emerge in order of increasing acid strength and decreasing 

Water solubility. An example is the formic, acetic, and propionic acid series. 

Dibasic acids elute sooner than nonbasic acids. Oxalic acid elutes before propionic acid. 

Unlike the pellicular packings used for ion exchange, the packings used in ion exclusion are derived from totally sulphonated polymeric materials. Separation is dependent upon three different mechanisms Dorman exclusion, steric exclusion and adsorption/partitioning. Dorman exclusion causes strong acids to elute in the void volumes of the column. Weak acids which are partially ionised in the eluent are not subject to Dorman exclusion and can penetrate into the pores of the packing. Separation is accomplished by differences in acid strength, size and 

Ion exclusion chromatography has been applied to the determination of the following organic compoimds and anions ozonisation products, carboxylic acids phosphate, nitrite, nitrate, silicate, bicarbonate, tartrate, malate, malonate, citrate, glycollate, formate and fumarate, arsenite, arsenate, chloride, bromide, iodide, thiocyanate and sulphate carbonate and also the cation arsenic. 

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Grosjean, D. J., Van Neste, A., and Parmar, S. S., Analysis of atmospheric carboxylic acids using single column ion exclusion chromatography with ultraviolet detection, J. Liq. Chromatogr., 12, 3007, 1989. 

Kwon, S.-M., Lee, K.-P., Tanaka, K., and Ohta, K., Simultaneous determination of anions and cations by ion-exclusion chromatography-cation-exchange chromatography with tartaric acid/18-crown-6 as eluent, /. Chromatogr. A, 850, 79, 1999. 

Carlson, M. and Thompson, R. D., Determination of borates in caviar by ion-exclusion chromatography, Food Additives Contaminants, 15, 898, 1998. 

Ng, K.L., Pauli, B., Haddad, P.R., and Tanaka, K., Retention modeling of electrostatic and adsorption effects of aliphatic and aromatic carboxylic acids in ion-exclusion chromatography, /. Chromatogr. A, 850, 17, 1999. 

Hioki et al. [215] have described an on-line determination of dissolved silica in seawater by ion exclusion chromatography in combination with inductively coupled plasma emission spectrometry. 

Klane and Blum [69] showed that inductively coupled plasma spectrometry was able to determine below 1000 ng/1 of arsenic in seawater. Ion exclusion chromatography coupled with inductively coupled plasma mass spectrometry has been used to determine several arsenic species in seawater [ 947 ]. Down to 3 ng/1 arsenic can be determined using hydride generation prior to this technique. 

Ion exclusion chromatography, of ascorbic acid, 25 760 Ion hopping, 14 469 Ionic aggregates, 14 463—466 Ionically conducting polymers, 13 540 Ionic carbides, 4 647 Ionic compounds, rubidium, 21 822 Ionic conduction, ceramics, 5 587-589 Ionic crystals, 19 185. See also Silver halide crystals... 

Steffeck, R.J. and Zelechonok, Y., Enantioselective ion-exclusion chromatography on teicoplanin aglycone and (-i-)-(18-crown-6)-2,3,ll,12-tetracarboxylic acid stationary phases, J. Chromatogr. A, 983, 91, 2003. 

Triethanolamine can be determined in metalworking and cutting fluids by gas chromatography-mass selective detection of silylated derivatives, by isotachophoresis, by capillary zone electrophoresis with indirect ultraviolet detection, and by spectrophotometry (Kenyon et al, 1993 Fernando, 1995 Schubert et al, 1996 Sollenberg, 1997) and in cosmetics and pharmaceuticals by ion-exclusion chromatography and by reversed-phase high performance liquid chromatography (Fukui et al, 1992 Maurer etal, 1996). 

Fukui, M., Konishi, H., Ohta, K. Tanaka, K. (1992) [Ion-exclusion chromatography with UV detection for the determination of alkanolamines in cosmetics using water-glycerine as an eluent]. Bunseki Kagaku, 41, T27-T31 (in Japanese)... 

In order to study birch lignosulfonates, spent sulfite liquor, from which monosaccharides had been removed by ion exclusion chromatography, was fractionated on the basis of molecular size by preparative GPC (Fig. 1). 

Sulfite and sulfate ions were precipitated from the spent birch liquor (Fig. 1) with barium hydroxide. Monosaccharides and other low molar mass non-electrolytes and weak electrolytes were separated quantitatively from the lignosulfonates by means of ion exclusion chromatography (5). 

In the initial stages of purification, sucrose is recovered in juice form by crushing cane stalks or by extraction of sliced sugarbeets (cossettes) with hot water. The resulting solutions are clarified with lime, then evaporated to thick syrups from which sugar is recovered by crystallization. The final syrup obtained after exhaustive crystallization of sucrose is known as molasses. Enhanced recovery of sucrose from beet molasses is accomplished by ion-exclusion chromatography, a process used in some sugar mills in the United States, Japan, Finland, and Austria. 

Glod, B.K. (1997). Ion exclusion chromatography parameters influencing retention. Neuro-chem. Res., 22(10), 1237-1248. 

The Donnan equilibrium is the basis of ion-exclusion chromatography. Because dilute electrolytes are excluded from the resin, they pass through a column faster than nonelectrolytes, such as sugar, which freely penetrates the resin. When a solution of NaCl and sugar is applied to an ion-exchange column, NaCl emerges from the column before the sugar. 

In ion-exclusion chromatography, ions are separated from nonelectrolytes by an ion-exchange column. Nonelectrolytes penetrate the stationary phase, whereas half of the ions are repelled by the fixed charges. Because electrolytes have access to less of the column volume, they are eluted before nonelectrolytes. The chromatogram here shows the separation of trichloroacetic acid (TCA, pKa = 0.5), dichloroacetic acid (DCA, pK.a = 1.1), and... 

K Tanaka, JS Fritz. Ion-exclusion chromatography of non-ionic substances with conductivity detection. J Chromatogr 409 271-279, 1987. 

WD Graham, D Annette. Determination of ascorbic and dehydroascorbic acid in potatoes (Solanum tuberosum) and strawberries using ion-exclusion chromatography. J Chromatogr 594 187-194, 1992. 

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