Determination of platinum by graphite furnace atomic absorption spectrometry in foods and beverages using an automated on-line separation-preconcentration system

The increasing use of automobile catalysts leads to the emission of the platinum-group elements (PGE), mainly platinum, but also rhodium and palladium into the environment. In environmental samples, the low concentration of platinum together with the high concentration of interfering matrix components often requires a preconcentration/enrichment step combined with a matrix-separation. The method employs on-line preconcentration of platinum on a column packed with silica gel functionalised with 1,5-bis(di-2-pyridyl)methylene thiocarbohydrazide (DPTH-gel) placed in the autosampler arm. The method has been applied to the determination of platinum in food and beverage samples with 93–110% recoveries in the range of 0.5–50 mg/kg for a range of spiked foods and 100–102% for spikes of 4 ng/ml for beverages.