New considerations about the separation and quantification of antimony species by ion chromatography–hydride generation atomic fluorescence spectrometry

• Published in: Journal of Chromatography A Vol. 1052; no. 1; pp. 121 - 129
• Main Authors: Miravet, R., López-Sánchez, J.F., Rubio, R.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.10.2004; Elsevier
• Subjects: Analysis; Analytical biochemistry: general aspects, technics, instrumentation; Analytical chemistry; Analytical, structural and metabolic biochemistry; Antimony - analysis; Antimony - isolation & purification; Antimony speciation; Atomic fluorescence spectrometry; Biological and medical sciences; Chemistry; Chromatographic methods and physical methods associated with chromatography; Chromatography, High Pressure Liquid - methods; Chromatography, Ion Exchange - methods; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General pharmacology; Gradient elution; Hydride generation; Hydrogen - chemistry; Ion chromatography; Medical sciences; Methylantimony species; Other chromatographic methods; Pharmacology. Drug treatments; Reference Standards; Reproducibility of Results; Sensitivity and Specificity; Spectrometry, Fluorescence - methods; Hydride generation; Methylantimony species; Ion chromatography; Atomic fluorescence spectrometry; Gradient elution; Antimony speciation; Elution; Gradient; Chemical analysis; Antimony; Hydrides; Speciation; Quantitative analysis
• ISSN: 0021-9673
• DOI: 10.1016/j.chroma.2004.08.021

A new method for the speciation of inorganic [Sb(III) and Sb(V)] and organic (Me 3SbCl 2) antimony species by using a polystyrene–divinylbenzene-based anion-exchange HPLC column (Hamilton PRP-X100) coupled to hydride generation atomic fluorescence spectrometry (HG-AFS) is presented. Several mobile phases were tested for the baseline separation of these three antimony species, investigating in detail experimental parameters such as concentration and pH. The best efficiency and resolution was achieved by using a gradient elution between diammonium tartrate 250 mmol l −1 pH 5.5 (A) and KOH 20 mmol l −1 pH 12 (B). The gradient programme used was 100% B for 1.5 min, decreasing to 0% B in 0.1 min and maintained the elution with 100% A for 5.5 min. Analysis time was less than 7 min. Equilibration of the column with the complexing mobile phase was found to be critical in order to avoid Sb(III) double peak formation. Dilution in diammonium tartrate medium was necessary in order to avoid Sb(III) oxidation at μg l −1 concentration level. Detection limits of 0.06 μg l −1 for Sb(V), 0.09 μg l −1 for Me 3SbCl 2 and 0.04 μg l −1 for Sb(III) as well as repeatability and reproducibility better than 5% R.S.D. ( n = 10) and 9% R.S.D. ( n = 30) (for 1 and 5 μg l −1 of Sb(V) and Sb(III) and 5 and 10 μg l −1 of Me 3SbCl 2) were obtained. Accuracy and recovery studies were carried out by analysing one river freshwater sample and two water certified reference materials. The proposed methodology can be considered reliable and straightforward for antimony speciation in fresh water samples.