A Chemical Modifier for the Determination of Selenium by Graphite Furnace Atomic Absorption Spectrometry and Its Application to Human Hair and Nails

A method for the determination of total selenium in human hair and nails using graphite furnace atomic absorption spectrometry (GF-AAS) with palladium/ascorbic acid as a chemical modifier is used. The effects of nickel nitrate, palladium/ ascorbic acid, and palladium/ magnesium nitrate as chemical modifiers on the sensitivity for the determination of selenite, selenate and selenomethionine by GF-AAS are compared. The palladium/ ascorbic acid modifier is used for the determination of total selenium in human hair and nails, because the oxidation states of selenium ion are not effective in the analysis . The detection limit of (GFAAS) is estimated to be 0.8 μg L-1 (calculated as 3s of the blank), and the calibration curve is linear for the concentration rang 5-50 μg L-1 and the recovery range is from 93.33 to 106 %. The optimal ashing and atomizing temperatures are 1300 degree C and 2250 degree C, respectively. The proposed method could be successfully applied to the determination of total selenium in human hair and nails.