Eluents copper sulfate

Fig. 1. Simultaneous separation and detection of anions and cations on a latex agglomerate column. Column Dionex HPIC-CS5 cation exchange column (250X2 mm) with precolumn HPIC-CG5 (50 X 4 mm) eluent 0.5 mM copper sulfate, pH 5. 62 flow rate 0.5 ml/min sample volume 20 gl containing 0.1 m M of each ion detection two potentiomet-ric detectors equipped with different ion-selective electrodes in series. Peaks (1) chloroacetate, (2) chloride, (3) nitrite, (4) benzoate, (5) cyanate, (6) bromide, (7) nitrate, (8) sodium, (9) ammonium, (10) potassium, (11) rubidium, (12) cesium, (13) thallium. Reprinted with permission from [10].

Fig. 2. Simultaneous separation of a model mixture of ions using anion exchange column coated with sulfopolysaccha-ride. Column TSK-Gel IC-Anion SW (100X0.32 mm) dynamically modified with heparin eluent 1 mM copper sulfate flow rate 4.2 Jil / min sample volume 0.2 jal detection UV 200 nm. Reprinted with permission from [11].

Indirect photometric detection was also utilized for cation determination. Fig. 6-19 illustrates the separation of sodium, ammonium, and potassium with copper sulfate as the eluent obtained by Small et al. [29]. Aromatic bases as cationic analogues to aromatic acids used in anion analysis are inappropriate as eluents for this detection method. As monovalent cations, they are already eluted by the oxonium ions. Thus, a significant absorption change is only observed when the protonated base cation contributes to the ion-exchange process. 

Fig. 6-19. Indirect photometric detection of sodium, ammonium, and potassium. - Separator column Dowex 50 eluent 0.005 mol/L copper sulfate flow rate 0.7 mL/min detection UV (252 nm, indirect) injection volume 20 pL solute concentrations 230 ppm sodium, 180 ppm ammonium, and 391 ppm potassium (taken from [29]).

Fig. 8-29. Trace analysis of chloride in an acid copper sulfate plating bath. — Separator column IonPac AS4 eluent 0.0028 mol/L NaHC03 + 0.0022 mol/L Na2C03 flow rate 2 mL/min detection suppressed conductivity injection 10 pL sample (1 1000 diluted).

Underivatized amino acids form complexes with copper(II). A variety of copper(II)-trapped phases have been developed for the enantiosepara-tion of amino acids. N-Salicylidene-(J )-2-amino-l,2-6is(2-buto Q -5-fe/t-bu(yl-phenyl)-3-phenyl-l-propanol was coated on an octadecyl-bonded silica gel column and copper sulfate solution was used as the eluent. The structure was constructed using the Molecular Editor program and optimized by MM2 calculations. The optimization was performed as the energy change was less than 10 kcal mol. The molecular weight of the chiral phase was 1449, and the final and van der Waals energies were 77.04 and —8.77 kcal mol, respectively. 

Aspartic and glutamic acids were not retained in a buffer solution without a counter-ion however, these acids were retained by the addition of octyl sulfate to the eluent, as seen in Figure 4.12. These amino acids can form a complex with copper ions and will be retained on the stationary phase. The addition of both a counter-ion and copper ions further increased the retention and made possible... 

Nitrophenyl Phenyl Tellurium5 Under nitrogen, 0.29 g (0.70 mmol) of diphenyl ditellurium are reduced with 0.03 g (0.73 mmol) of sodium borohydride in 5 ml of hexamethylphosphoric triamide at 70-80° with stirring for 0.5 h. Then 0.14 g (0,73 mmol) of copper(l) iodide are added whereupon the mixture turns black. 0.18 g (0.73 minol) of l-iodo-2-nitrobenzene are added and the mixture is stirred well and heated at 80 90° for 1.5 h. The mixture is cooled, water is added, the whole is extracted with diethyl ether, the extract is washed with concentrated sodium chloride solution, and the organic layer is dried with anhydrous sodium sulfate. The solvent is evaporated under vacuum and the residue is chromatographed on a short column of alumina with hexane as eluent. Fractions containing the product are combined and evaporated to dryness and the residue is rccrystallized from ethanol yield 0.22 g (95%) m.p. 94°. 

Figure 2 Analysis of eight amino acid racemates. Chromatography conditions column MCI GEL CRS10W, eluent O.Smmoir copper (II) sulfate, flow rate 1.0 ml min , detection 254 nm, peaks 1 o-Ala, 2 i-Ala, 3 o-Pro, 4 o-Val, 5 L-Pro, 6 L-Val, 7 o-Leu, 8 o-NIe, 9 D-Tyr, lOi-Leu, 11 o-Eth, 12i-Tyr, 13L-Nle, 14o-Phe, 15L-Eth, 16L-Phe. (Reproduced with permission from Weston A and Brown Ph (1997) HPLC and CE - Principles and Practice. Academic Press, p. 61 Eisevier.)...

Figure 10.162 Determination of chloride in an conductivity injection volume 25 pL sample acid copper bath. Separator column lonPac acid copper bath (diluted 1 100) peaks (1) AS15 eluent 30 mmol/L KOH (EG) flow rate unidentified, (2) 0.47 mg/L chloride, (3) car-1.2 mlVmin detection suppressed bonate, and (4) sulfate.

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