Chelidamic acid as a new eluent for the determination of Fe(II) and Fe(III) species and other metals by high performance chelation ion chromatography

The chelidamic acid (CDA) is proposed as a new eluent reagent in high performance chelation ion chromatography for the simultaneous isocratic separation of Fe²⁺ and Fe³⁺, Mn²⁺, Pb²⁺, Cd²⁺, Zn²⁺, Co²⁺ and Cu²⁺ on an iminodiacetic acid functionalized silica column 150 × 4.0 mm i.d., with an optimized eluent composed of 2 mmol L^-1 CDA, 3 mmol L^-1 triethanolamine, 12 mmol L^-1 HCl, and 50 % v/v of methanol at flow rate of 0.5 mL min^-1. Post-column reaction with 4-(2-Pyridylazo) resorcinol (PAR) was used for sensitive spectrophotometric detection at 510 nm. The developed method is suitable for the quantitative speciation of iron as well as for the determination of other metals. The applicability of this method to the direct analysis of fuel ethanol was demonstrated.