HG-AFS Determination of Selenium in Dried Mushrooms

HG-AFS was applied to the determination of Selenium in dried mushrooms.Dried mushroom sample was digested with conc.HNO3.The solution was evaporated to ca.2 mL,and kept boiling gently for 3-5 min after addition of 10 mL of 6 mol·L-1 HCl to reduce Se(Ⅵ) completely to Se(Ⅳ).An aliquot of the sample solution was taken for the HG-AFS determination after addition of K3Fe(CN)6.Hydride generation was performed in 5 g·L-1 KOH medium with 20 g·L-1 of KBH4.Standard curve with mass concentration of Se(Ⅳ) in the range within 60 μg·L-1 was used for the determination.Detection limit (3s/k) found was 0.26 μg·L-1.The proposed method was used to analyze a CRM of wheat powder (GBW 085036),giving the analytical result of Se 0.046 μg·g-1,which is in consistency with the certified value (0.049±0.014) μg·g-1,and the value of RSD (n=6) found was 2.1%.