Application of colloidal palladium modifier for the determination of As, Sb and Pb in a spiked sea water sample by electrothermal atomic absorption spectrometry

摘要

Colloidal palladium was used as a chemical modifier for analysis of complex samples by electrothermal atomic absorption spectrometry. In order to demonstrate high potnetial of the modifier, optimization of the time-temperature program of the atomizer was limited with only pyrolysis and atomization temperatures, Fixed palladium modified masses were applied (6 #mu#g for pure analyte solutions and 15 #mu#g for matrix-containing solutions). It was shown that in the presence of colloidal palladium, interference-free determinations of As, Sb and Pb are possible up to at least 450 #mu#g of chloride ion, or 40 #mu#g of sulfate ion (as their sodium salts) in the atomizer. Colloidal palladium was used for the direct determination of As, Sb and Pb in a spiked sea water sample (from Bosphorus channel near istanbul) by means of the calibration graphs prepared with pure analyte solutions. The detection limits for As, Sb and Pb in a sea water matrix calculated according to 2#sigma# criteria are 5.4, 3.6 and 1.1 ng ml~(-1), respectively (for sample volume 10 #mu#l). In unspiked sea water, the contents of As, Sb and Pb were found to be below the detection limits. Recoveries of spiked analytes (25 and 50 ng ml~(-1)) were in the region of 98-112% depending on the nature of analyte and the concentration of spike.