Cathodic stripping voltammetric determination of platinum in some foods and beverages at ng/g level under statistical control

This work was aimed to evaluate the capabilities of Catalytic Adsorptive Stripping Voltammetry in quantifying platinum at mg/kg level or lower, under statistical control, in some samples of foods and beverages. Samples of tap water, rosé wine in tetrabrik package, bottled white wine, canned lemon tea, camomile in filter bags, peach fruit juice, UHT semi-skimmed milk, wild chicory and bottled red wine (1985 vintage), as well as the in-house aqueous standard solutions containing 2,0 mg/kg of platinum (used in statistical control), were microwave mineralized. Platinum was quantified at concentration levels lower than 1 mg/kg in tap water, canned lemon tea, camomile in filter bags, UHT semi-skimmed milk and wild chicory. In rosé wine in tetrabrik package and bottled white wine the analyte concentration was at mg/kg level, while in the bottled red wine and in the peach fruit juice was not significantly different from zero. Owing to the outstanding sensitivity of the used method, the reproducibility and the precision (expressed as confidence interval at 95% confidence level) of all the results were surprisingly good.