Determination of Disodium Ethylene Diaminetetraacetate in SamplesBased on Ion Chromatography with In Guard H Column

Abstract

A method for the determination of EDTA was developed and validated based on ion chromatography with suppressed conductimetric detection and anion exchange column.The pre-concentration of EDTA was obtained on In guard H by using pump and ten ports valve,then the optimization separation condition was performed on a IonPac AS22(250 mm×4.0 mm) using 4.5 mmol/L carbonate and 1.4 mmol/L bicarbonate buffer solution with 18% acetonitrile as the mobile phase with Isocratic elution.Good resolution was achieved from commonly coexisting anions and organic acid.The interference of different metal cations(Ca2+,Mg2+,Cu2+,Zn2+ and Fe3+) and the increase of molar ratio were also examined.The ion chromatographic method was applied for the assay of EDTA in contact lens care solutions、salad and canned foods with simple treatment.The linear range of EDTA was 0.6-50 mg/kg.The recovery of EDTA was about 91.2%-97.0%.