Multi-elemental analysis of mussel samples by atomic absorption spectrometry after room temperature sonication
A simple procedure was developed for the room temperature leaching of several elements from mussel samples with a solution of 1.6 M HNO3, 1.2 M HCl and 0.1 M H2O2. The method involves the use of a sonication time of 120 min and determination by flame (FAAS) and electrothermal atomic absorption spectrometry (ETAAS). Ca, Cu, Fe, K, Mg, Mn, Na, V and Zn were quantitatively recovered and Cd, Co, Cr, Rb and Se were partially leached; the leaching of Cs and Sc was poor. The effect of sample mass, reagent leaching mixture and sonication time on the extraction of the elements was evaluated from the direct analysis of the acidic phase by AAS and of the remaining solids by neutron activation analysis. The results obtained by the proposed procedure were evaluated by comparison with those obtained by ICP-MS and AAS after microwave-assisted digestion and also with those found by direct analysis of the solid sample by neutron activation. The method provides a limit of detection of 0.081, 0.012, 0.059, 0.002 and 0.007 µg ml–1 for Ca, Cu, Fe, Mg and Zn, respectively, and 0.342 ng ml–1 for Mn, and RSD values from 0.6 to 7.1% as a function of the element concentration. The recovery values found in the analysis of spiked samples ranged from 92 to 109%, and relative errors lower than 9% were found in the analysis of a certified mussel tissue.