Determination of Selenium in Biological Samples by Flame Atomic Absorption Spectrometry after Preconcentration on Modified Polyurethane Foam

An analytical method has been proposed based on the separation and determination of selenium(IV) ion using polyurethane foam as a solid sorbent coated with ammonium pyrrolidine dithiocarbamate (APDC). Different factors including the pH of sample solution, time of extraction, volume of sample, and amount of the loaded and unloaded polyurethane foam were examined and a preconcentration factor of 5 was obtained. The interference effects of some additional salts in the solution such as NaCl, FeCl3, BaCl2, CH3COONa and Na2SO4 have been investigated. The improved limit of detection (LOD) for the method is 0.064 mg/L. The improved LOD is much lower than the LOD of FAAS and approaching the LOD of GFAAS. The new developed procedure SPE-FAAS has been Found to be successful in separating the complex matrices (human hair, bovine liver, pork liver, bovine muscle) and preconcentrating selenium ion from real blood sample. The developed method for solid-liquid extraction is convenient, simple, sensitive and of low costs.