Flow injection on-line pre-concentration of platinum coupled with electrothermal atomic absorption spectrometry

A method for on-line pre-concentration of platinum with subsequent determination by electro-thermal atomic absorption spectrometry (ETAAS) has been developed. After a preliminary treatment of the sample solution with tin(II)-chloride the formed anionic Pt–Sn complexes were on-line adsorbed on a C18 micro column which has been reversibly loaded with the chelating agent N,N-diethyl-N′-benzoylthiourea. The formed platinum complex was eluted with ethanol and directly introduced into the graphite furnace. Using a sample volume of 1.57 mL the limit of detection was calculated to be 0.1 μg L−1. The reproducibility of the method given as the relative standard deviation was 5.5% at a concentration level of 0.5 μg L−1 Pt (n = 10). The accuracy of the developed method has been demonstrated by the analysis of the certified reference material BCR-723 (road dust). The new method has been applied to the analysis of platinum in aerosol samples collected in a highway-tunnel in Vienna, Austria.