Analytical Sciences


Abstract − Analytical Sciences, 18(5), 571 (2002).

Application of 5,10,15,20-Tetrakis(4-carboxyphenyl)porphine for Cadmium Preconcentration in Flow-Injection System
Krzysztof KILIAN and Krystyna PYRZYNSKA 
Warsaw University, Department of Chemistry, Pasteura 1, 02-093 Warsaw, Poland
The suitability of 5,10,15,20-tetrakis(4-carboxyphenyl)porphine as a complexing agent for the on-line preconcentration of cadmium using an anion exchanger (Amberlite IRA-904) in a microcolumn has been tested. Various parameters which affect complex formation and its sorption, as well as elution into the nebulizer of flame atomic absorption spectrometry (FAAS), were optimized. A 5 x 10-4 mol l-1 reagent was on-line mixed with an aqueous sample solution and flowed through the microcolumn for 2 min. The sorbed complexes were then eluted with 2 mol l-1 of nitric acid into the nebulizer of FAAS. A good precision (2.1% RSD for 40 ug l-1 cadmium) and a high enrichment factor (36) with a detection limit (3 sigma) of 1.4 ug l-1 were obtained. The achieved analytical results for a standard reference material (SRM 1643d) were in good agreement with the certified values.