DETERMINATION OF SELENIUM IN SEAFOODS USING ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRY WITH SLURRY SAMPLE INTRODUCTION

An electrothermal atomic absorption spectrometric procedure for the ra pid 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 co ncentrated hydrogen peroxide, 1% v/v concentrated nitric acid, and 0.0 8 g of nickel nitrate. A fast-heating program, with no ashing or clean ing stage, is used. By introducing a delay time of 1 s between the sta rt of atomization and the start of the measurement of the integrated a bsorbance, reliable results are obtained using a spectrometer equipped with a deuterium-arc background corrector. Simple aqueous standards a re used for calibration. The results agree with those obtained by hydr ide generation atomic absorption spectrometry. The detection limit is 0.2 mu g/g of selenium when using the maximum recommended percentage o f 1% w/v for the slurry preparation.