Abstract:

A method for the determination of selenium in infant formulas was developed using microwave digestionhydride
generation atomic fluorescence spectrometry. Effects of reagents, pre-reducing methods, the presence or absence of
potassium ferricyanide, and reserving time of the sample digestion solution of certified reference material and the reducing
agent on the test results of selenium were studied. Under the appropriate reagent and pre-reducing condition, without using
potassium ferricyanide as masking agent, the linear regression equation was I = 38.440 4C＋1.362 7 in the linear range
of 1.0–10 ng/mL (r = 1.000 0). The limit of detection (LOD) was 0.084 ng/mL, and the recovery rate of selenium from
spiked samples was 90.4%–109%, with relative standard deviation (RSD) of 2.9% (n = 6). The digestion solution of the
certified reference material GBW10017 (GSB-8 milk powder) could be stored at room temperature for three days before
determination and the reducing agent was valid within at least one week under refrigeration. The method was characterized
by simple operation, high efficiency, reagent-saving, easy operation and no pollution, and was suitable for rapid and accurate
determination of selenium in infant formulas.

Key words: microwave digestion, hydride generation atomic fluorescence, infant formula, selenium