Simultaneous determination of Ba, Co, Fe, and Ni in nuts by high-resolution continuum source atomic absorption spectrometry after extraction induced by solid-oil-water emulsion breaking.

This paper describes the simultaneous determination of Ba, Co, Fe, and Ni in nuts by high-resolution continuum source atomic absorption spectrometry after extraction induced by solid-oil-water emulsion breaking. Extraction yields ranged from 94.9 for Ba to 109.8% for Fe. Simultaneous measurements were carried out at secondary lines of Ba, Co, Fe, and Ni. The limits of detection and quantification were, respectively, 3.819 and 1.146 mg L for Ba, 2.274 and 7.421 µg L for Co, 0.095 and 0.285 mg L for Fe, and 2.138 and 6.614 µg L for Ni. The precision ranged from 3.1 to 4.2%, 1.5 to 8.0%, 1.6 to 6.6%, and 0.4 to 6.1% for Ba, Co, Fe and Ni, respectively. The method accuracy was assessed by recovery tests and comparison of the results obtained by the proposed extraction method with those obtained after acid digestion. Recoveries ranged from 93.5 for Ni to 104.5% for Co.