DETERMINATION OF SELENIUM IN WHEAT-FLOUR BY GFAAS USING AUTOMATED ULTRASONIC SLURRY SAMPLING

A simple method is described for the determination of Se by GFAAS. The method uses a Pd + Mg matrix modifier, isothermal atomization, and au tomated slurry mixing. Slurries are prepared by weighing an amount of the solid sample and adding 1 mL of an acidic diluent containing 0.005 % Triton X-100. The proposed method provides both good accuracy and pr ecision without the need for acid digestion or ashing of the sample, w hich could cause selenium loss. The NIST SRM 1567a wheat flour and fiv e commercial wheat flour samples were analyzed to determine Se. The re peatability of the method using a 5% (m/v) slurry was 8.2% and the det ection limit was 0.06 mug/g Se.