Immobilized 1,5-diphenylcarbazone as a complexing agent for on-line trace enrichment and determination of copper by flow injection-atomic absorption spectroscopy

Abstract

A rapid on-line preconcentration technique for the determination of copper in different samples by FI-AAS has been devised. Preconcentration is based on the deposition of analyte on a micro-column of 1,5-diphenylcarbazone immobilized on surfactant coated alumina and subsequent elution by injection of a small volume of hydrobromic acid (500 µl of 0.75 mol l⁻¹acid). A sample volume of 30 ml resulted in a preconcentration factor of 100, and precisions at the 100 and 10 µg l⁻¹ levels were 3.2 and 3.5% RSD, respectively. The procedure was applied to spring water, well water, sea-water, stainless steel and a multivitamin tablet and the accuracy was assessed through recovery experiments, independent analysis by furnace-AAS, and the analysis of a certified reference material.