title: Development of an analytical method for antimony speciation in vegetables by HPLC-hydride generation-atomic fluorescence spectrometry.
abstract: A new method for antimony speciation in terrestrial edible vegetables (spinach, onions, and carrots) was developed using HPLC with hydride generation-atomic fluorescence spectrometry. Mechanical agitation and ultrasound were tested as extraction techniques. Different extraction reagents were evaluated and optimal conditions were determined using experimental design methodology, where EDTA (10 mmol/L, pH 2.5) was selected because this chelate solution produced the highest extraction yield and exhibited the best compatibility with the mobile phase. The results demonstrated that EDTA prevents oxidation of Sb(III) to Sb(V) and maintains the stability of antimony species during the entire analytical process. The LOD and precision (RSD values obtained) for Sb(V), Sb(III), and trimethyl Sb(V) were 0.08, 0.07, and 0.9 microg/L and 5.0, 5.2, and 4.7%, respectively, for a 100 microL sample volume. The application of this method to real samples allowed extraction of 50% of total antimony content from spinach, while antimony extracted from carrots and onion samples ranged between 50 and 60 and 54 and 70%, respectively. Only Sb(V) was detected in three roots (onion and spinach) that represented 60-70% of the total antimony in the extracts.
authors.affiliation: Pontificia Universidad Cató1ica de Valparaíso, Laboratorio de Quimica Analitica y Ambiental, Instituto de Química, Avenida Brasil 2950, Valparaiso, Chile.
authors.forename: David
authors.initials: D
authors.lastname: Olivares
authors.forename: Manuel
authors.initials: M
authors.lastname: Bravo
authors.forename: Jorg
authors.initials: J
authors.lastname: Feldmann
authors.forename: Andrea
authors.initials: A
authors.lastname: Raab
authors.forename: Alexander
authors.initials: A
authors.lastname: Neaman
authors.forename: Waldo
authors.initials: W
authors.lastname: Quiroz
mesh_terms: D000965:Antimony / Q000032:analysis*; D002614:Chelating Agents / Q000494:pharmacology; D002623:Chemistry Techniques, Analytical / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D018552:Daucus carota; D004492:Edetic Acid / Q000737:chemistry; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis; D007202:Indicators and Reagents; D019697:Onions; D018517:Plant Roots; D015203:Reproducibility of Results; D012996:Solutions; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013054:Spectrophotometry, Atomic / Q000379:methods*; D018724:Spinacia oleracea; D014465:Ultrasonics; D014675:Vegetables / Q000378:metabolism*
chemical_list: D002614:Chelating Agents; D007202:Indicators and Reagents; D012996:Solutions; D004492:Edetic Acid; D000965:Antimony