Determination of selenium in seafoods using electrothermal atomic absorption spectrometry with slurry sample introduction

An electrothermal atomic absorption spectrometric procedure for the rapid determination of selenium in seafoods without previous dissolution of the samples is discussed. The lyophilized samples are suspended in 5 mL of double-distilled water containing 10% v/v ethanol, 10% v/v concentrated hydrogen peroxide, 1% v/v concentrated nitric acid, and 0.08 g of nickel nitrate. A fast-heating program, with no ashing or cleaning stage, is used. By introducing a delay time of 1 s between the start of atomization and the start of the measurement of the integrated absorbance, reliable results are obtained using a spectrometer equipped with a deuterium-arc background corrector. Simple aqueous standards are used for calibration. The results agree with those obtained by hydride generation atomic absorption spectrometry. The detection limit is 0.2 mu g/g of selenium when using the maximum recommended percentage of 1% w/v for the slurry preparation.