Copper, iron and zinc determinations in human milk using FAAS with microwave digestion

A method for determining copper, iron and zinc in human milk was optimized and validated. It includes microwave mineralization of the sample and measuring the elements by flame atomic absorption spectroscopy (FAAS). Only 2 ml of milk is needed, and the method is free of matrix interferences. The values obtained for the detection limits (0.07; 0.07; 0.11 mu g/ml milk, for copper, iron and zinc) precision of the method, intra-assay (2.9; 5.2; 6.1% RSD for copper, iron and zinc) and accuracy, evaluated using recovery assays (98.8; 100.4; 95.9% for copper, iron and zinc) show that the method is useful for the purpose mentioned. Moreover, the method is rapid and simple, and the determinations are carried out by FAAS. (C) 1999 Elsevier Science Ltd. All rights reserved.