Optimization of selenium determination in human milk and whole blood by flow injection hydride atomic absorption spectrometry.

abstract A flow injection hydride atomic absorption spectrometry (FI-HAAS) method was developed for determining selenium in human milk and whole blood after microwave digestion of the sample. The sample (2 mL human milk or 0.25 mL blood) was introduced into the microwave vessel with 1.5 mL HN03 and 0.25 mL H202 and 300 W (4 min) and 600 W (4 min) were applied. The digestion was completed by heating to 140 C (2-3 h). Se (VI) was reduced to Se (IV) with hydrochloric acid. The instrumental conditions for FI-HAAS (concentrations of reducing agent and carrier acid, flow rate of argon carrier gas, and sample volume injected) were optimized. The detection limit of the proposed method was 0.23 ng/m…