Separation and enrichment of palladium and gold in biological and environmental samples, adapted to the determination by total reflection X-ray fluorescence

The reductive co-precipitation of trace and ultra-trace elements together w ith mercury followed by complete evaporation of the mercury makes it possib le to determine palladium and gold by total reflection X-ray fluorescence. Both elements can be detected without interferences at optimal sensitivity in the pg range. Thus, detection limits of, e.g., 2.5 ng L-1 for palladium and 2.0 ng L-1 for gold, in urine, were obtained. The precision was determi ned to 0.04 at a palladium concentration of about 200 ng L-1 urine and to 0 .19 at a gold concentration of only 18 ng L-1. The recovery for a urine sam ple spiked with known amounts of palladium and gold amounted to > 95%. Resu lts of the combined procedure are given for the determination of palladium and gold in the urine of non-exposed and occupationally exposed persons and in some other environmentally relevant samples.