Development of new analytical method for preconcentration/speciation of inorganic antimony in bottled mineral water using FIA-HG AAS system and SiO2/Al2O3/SnO2 ternary oxide

In the present paper, a new analytical preconcentration/speciation method for antimony species determination in bottled mineral water samples using the SiO2/Al2O3/SnO2 adsorbent was developed. The method is based on selective adsorption of Sb(III) ions by SiO2/Al2O3/SnO2 under a wide pH range (2.5–7.5). Total antimony was determined with previous sample treatment using 0.1% (w/v) L-cysteine and the concentration of Sb(V) species was determined by the difference between total and Sb(III). The proposed method provided an analytical curve ranging from 0.50 to 5.00 μg L−1 (r = 0.999), limit of detection (LD) of 0.17 µg L−1 and preconcentration factor (PF) of 136-fold. The method exhibited tolerance to different metal ions and the accuracy was attested from addition and recovery tests (95.2–106.0%) in bottled mineral water samples using 2.0% (w/v) L-cysteine, as well as by analysis of certified material. Only Sb(III) species were determined in mineral water (0.54–1.04 μg L−1).

Palavras-chave

Bottled mineral water, Flow injection hydride-generation flame atomic absorption spectrometry, Full factorial design, L-Cysteine, Stibine, Total antimony