The multivariate optimisation of ultrasonic bathinduced acid leaching for the determination of trace elements in seafood products by atomic absorption spectrometry

The effects of several variables on the As, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Pb, Se and Zn ultrasonic bath induced-acid leaching from lyophilised seafood samples have been studied by experimental designs. The determinations were carried out by electrothermal atomic absorption spectrometry (As, Cd, Co, Cr, Mn, Pb and Se), flame atomic absorption spectrometry (Ca, Cu, Fe, Mg and Zn) and by cold vapour-atomic absorption spectrometry (Hg). A Plackett-Burman experimental design was used to select the most significant variables that affect to the acid leaching process, while central composite designs were used to found optimum values for the variables involved in the acid leaching. The optimum conditions found for each variable and each element were tabulated. Accurate results were obtained by measuring DORM-1, DOLT-1 and TORT-1 certified reference materials, and the procedure was finally applied to mussel, clam and tuna samples