Latex anion exchanger

Fig. 3-21. Elution profile of the IonPac AS9 latex anion exchanger. - Eluent 0.00075 mol/L NaHC03 + 0.002 mol/L Na2C03 flow rate 1 mL/min detection suppressed conductivity injection volume 50 pL solute concentrations 1 ppm fluoride, 5 ppm chlorite, 1.5 ppm chloride, 6 ppm nitrite, 10 ppm bromide, 15 ppm chlorate and nitrate, 20 ppm orthophosphate and sulfite, and 25 ppm sulfate.

Another example of the high selectivity of a latexed anion exchanger for the analysis of structurally isomeric oligosaccharide side chains of a glycoprotein is the chromatogram in Fig. 3-121. It shows the separation of mannose hexamers with terminal N-... 

The corresponding AminoPac PA-1 latex anion exchanger consists of a polystyrene/ divinylbenzene substrate with a particle diameter of 10 pm. The synthesis of the latex beads is carried out, however, using dimethylamine instead of divinylbenzene for crosslinking the polymer. Until now, no methods have been available for the separation... 

Fig. 4-22. Separation of a hydrolysate standard on a latex anion exchanger AminoPac PA-1. -Eluent (A) 0.028 mol/L NaOH + 0.008 mol/L Na2B407, (B) 0.07 mol/L NaOH + 0.02 mol/L Na2B407, (C) 0.16 mol/L NaOAc, (D) 0.32 mol/L NaOAc, regenerent 0.56 mol/L NaOH + 0.64 mol/L H3B03 flow rate 1 mL/min detection see Fig. 4-19 injection 1 nmol of each of the various amino acids.

Fig. 4-23. Separation of arogenic acid on a latex anion exchanger. — Chromatographic conditions see Fig. 4-22.

An important constituent in copper pyrophosphate baths is nitrate, which enhances the maximum permissible current density [31]. Fig. 8-30 shows the respective chromatogram with the separation of nitrate and orthophosphate. The latter is the hydrolysis product of pyrophosphate that is formed during the plating process. The main component pyrophosphate may also be separated on a latexed anion exchanger. It is detected after complexation with ferric nitrate in a post-column reaction by measuring the light absorption (see Section 3.3.5.2). 

When it was introduced, the lonPac AS12A was clearly the most modem latexed anion exchanger for the separation of fluoride, oxyhalides, and mineral acids. The latest development in the field of universal anion exchangers for water analysis is the lonPac ASM discussed in Section 3.4.1, which is based on a support material with a covalently bonded ion-exchange polymer (see Fig. 3-33 in Section 3.4.1). 

Fig. 3-202. Separation of amino acids on an AminoPac PA-10 latexed anion exchanger (250 X 2 mm i. d.). - Eluant NaOH — sodium acetate gradient see Table 3-31 flow rate 0.25 mL/min detection integrated amperometry on a gold working electrode analytes 100 pmol each of arginine (1),...

The introduction of the lonPac CS5 separator column [28] in the mid-1980s finally remedied the problems associated with the determination of iron(III). The CS5 column is a latexed anion exchanger with mixed anion and cation... 

The corresponding AminoPac PA-1 latexed anion exchanger, introduced at the same time as the AminoPac PC-1, has been replaced meanwhile by a more modern product, the AminoPac PA-10 (see Section 3.11). The baseline-resolved separation of 17 amino acids contained in a hydrolysate standard requires about 40 minutes, which is significantly longer than with a latex cation exchanger. 

Fig. 7-9. Separation of monosaccharides in a chocolate milk on a latexed anion exchanger a) with pulsed amperometric detection at a gold working electrode, b) with conventional amperometric detection applying a constant working potential. Analytes (1) glucose, (2) fructose, (3) lactose, and (4) sucrose.

Heitkemper et al. [99] applied element-specific detection for the simultaneous determination of arsenic(III)/arsenic(V) in food additives. The separation shown in Fig. 7-49 was obtained on a latexed anion exchanger with a NaOH eluant. 

Polyphosphonic acids are separated on a special latexed anion exchanger and detected photometrically after complexation with iron(III) nitrate [109] (see Section 3.8.2). With this method qualitative analysis of inorganic and organic phos-... 

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