GF-AAS Determination of Trace Amount of Beryllium in Soil and Agricultural Products

Soil sample was digested with conc.HNO3 and H2O2 in the ETHOS 1 microwave digestor under the prescribed program.The solution obtained was evaporated to near dryness and its volume was made up to 25.0 mL,which is ready for the GF-AAS analysis.Sample of agrucultural products was soaked in conc.HNO3 and HClO4 over night,and then heated on an electric hot plate until color of the solution became dark brown.A definite amount of mixed acid of HNO3 and HClO4 (3+1) was added to the solution and evaporated to fumes of HClO4 acid.The solution was cooled,diluted to 25.0 mL and ready to be used for GF-AAS analysis.Ten μL of sample solution were taken and its beryllium content determined by GF-AAS under the prescribed instrumental working condition.Calcium salt solution was added as matrix modifier.Linear relationship between values of absorbance and mass concentration of Be(Ⅱ) was obtained in the range within 4.0 μg· L-1 with the detection limit (3s/k) of 0.4 pg.The proposed method was used in the determination of beryllium in CRM′s of soil and spinach,giving results in consistency with the certified values,with RSD′s (n=6) less than 5%.