Abstract
Copper and iron were extracted on-line from solid seafood samples by a robust, fast and simple continuous ultrasound-assisted extraction system (CUES). CUES is connected to a flow-injection manifold, which allows on-line flame atomic absorption spectrometric determination of copper and iron. Experimental designs were used to optimize the continuous leaching procedures. These methods allowed a total sampling frequency of 46 and 18 samples per hour, with relative standard deviations of 1.6% and 0.3%, for copper and iron, respectively (for a sample containing 13.6 µg/g of copper and 217.3 µg/g of iron (dry mass)). The limits of detection for 30 mg of sample were 0.3 µg/g for copper and 0.6 µg/g for iron (dry mass). Analytical procedures were verified by the analysis of a standard reference material (lobster hepatopancreas marine, TORT-1) and were applied to several real seafood samples from the estuaries of Galicia (Spain) with satisfactory results.
Acknowledgements
The authors are grateful for the financial support provided by the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ministerio de Ciencia y Tecnología (Project no. CAL01-043). A.M.C.B. acknowledges a grant from the Ministerio de Educación, Cultura y Deporte, Ap 2001-0367.