Separation selectivity of anionic metal complexes of N,N'-bis(hydroxybenzyl)ethylenediamine-N,N'-diacetic acid in ion and ion electrokinetic chromatography
Ov. Krokhin et al., Separation selectivity of anionic metal complexes of N,N'-bis(hydroxybenzyl)ethylenediamine-N,N'-diacetic acid in ion and ion electrokinetic chromatography, J CHROMAT A, 895(1-2), 2000, pp. 255-261
The complexes of Fe(III), Co(III), Mn(III), Al(III), Cu(II), Ni(II), Cd(II)
and Zn(II) with N,N'-bis(hydroxybenzyl)ethylenediamine-N,N'-diacetic acid
(HBED) were separated by ion exchange in different modes: ion chromatograph
y (IC) and ion electrokinetic chromatography (IEKC). In column IC these com
plexes were separated on an IonPac AS4a anion-exchange column (Dionex, USA)
. Parameters of the background electrolyte that were examined in IEKC mode
include polymer, competing ion concentration and pH. The use of poly(dially
ldimethylammonium chloride) (PDADMACl) as a modifier in IEKC provides separ
ation selectivity only slightly different from that observed in IC on the I
onPac AS4a column. Optimal separation conditions were found to be: 0.1 mM H
EED, 50 mM PDADMAOH, 10 mM Na2B4O7, pH adjusted to 10 with acetic acid. The
use of an aromatic ligand allowed a 10-fold decrease in detection limits o
f metal ions in comparison with previously studied EDTA. A separation effic
iency up to 400 000 theoretical plates was demonstrated for IEKC. (C) 2000
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