Determination of Selenium in Black Peanut by Graphite Furnace Atomic Absorption Spectrometry

KeyWord:graphite furnace atomic absorption spectrometry  black peanut  selenium

Abstract:

      The trace levels of selenium content in black peanuts were determined by graphite furnace atomic absorption spectrometry£¨GF AAS£©. The sample was ingested with high pressure closed vessel using nitric acid-hydrogen peroxide as solvent. Pd£¨NO3£©2+Mg£¨NO3£©2 were selected as chemical modifiers to increase the thermostability of selenium, and the pyrolysis temperature and the atomization temperature for the experiments were seted at 500 ¡æ and 2 000 ¡æ, respectively. Under the optimal conditions, the calibration curve showed a good linear relationship between the adsorption peak area and selenium concentration in the range of 10-200 ¦Ìg?L-1 with a detection limit£¨3¦Ò£© of 8ª±78 ¦Ìg?L-1.The relative standard deviation£¨n=11£© of blank sample was 4ª±6%, and the recoveries varied from 96% to 113%. The result also indicated that the kernels and coats of black peanuts contained trace selenium and their contents were higher than those of other two local peanuts.