Determination of copper in infant formula by graphite furnace atomic absorption spectroscopy with a L'vov platform

A rapid method for the determination of sub-part-per-million levels of copper in infant formula, which does not require decomposition of the sample matrix before analysis, has been developed. The method uses L'vov platform graphite furnace atomic absorption spectroscopy (GFAAS), a technique that greatly reduces matrix interferences limiting the applicability of normal GFAAS. The sample preparation consists of dilution of a weighed sample of infant formula to a known volume with a 0.5% solution of Triton X-100 in deionized water. The accuracy of the method, as assessed from the results of overspike recovery studies (96.5-101.3% recovery) for different matrix types and comparison to results generated with alternative methodologies, can be considered excellent. The overall precision of the method ranges from 2.5 to 4.3% RSD for different matrix types.