Speciation analysis of inorganic antimony in soil using HPLC-ID-ICP-MS.
Speciation analysis of Sb(III) and Sb(V) in a soil sample was performed through extraction and on-line isotope dilution concentration determination after a chromatographic separation. The total Sb concentration found in a through traffic contaminated soil sample was (4.17 microg g(-1), 0.3 microg g(-1) SD, n=6). It was determined using ICP-MS after soil digestion using the sodium peroxide sintering method. The optimized extraction procedure for speciation analysis was carried out using 100 mmol L(-1) citric acid at pH 2.08 by applying an ultrasonic bath for 45 min at room temperature. The effects of citric acid concentration (0-500 mmol L(-1)), pH (1-6), and temperature (30-60 degrees C) on inorganic antimony species distribution in the examined sample were studied and optimized. The separation of Sb(III) and Sb(V) was achieved using an anion exchange column (PRP-X100) and 10 mmol L(-1) EDTA and 1 mmol L(-1) phthalic acid at pH 4.5 as a mobile phase. The eluent from the HPLC was mixed with an enriched (94.2%) (123)Sb spike solution that was pumped by a peristaltic pump with a constant flow rate (0.5 mL min(-1)) in a three-way valve. The blend passed directly to the Conikal nebulizer of the ICP-MS. By using the above extraction procedure and methodology, 43.2% Sb(V) (2.9% RSD, n=3) and 6.0% Sb(III) (1.3% RSD, n=3) of total Sb found in the sample could be detected. The detection limits achieved by the proposed method were 20 ng L(-1) and 65 ng L(-1) for Sb(V) and Sb(III), respectively. The precision, evaluated by using RSD with 100 ng L(-1) calibration solutions, was 2.7% and 3.2% (n=6) for Sb(V) and Sb(III), respectively, in aqueous solutions.
Amereih
Sameer
S
General and Analytical Chemistry, University of Leoben, Franz-Josef-Strasse18, 8700, Leoben, Austria. Sameer.Amereih@notes.unileoben.ac.at
Meisel
Thomas
T
Kahr
Elisabeth
E
Wegscheider
Wolfhard
W
D000965:Antimony / Q000032:analysis* / Q000737:chemistry; D002412:Cations; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002852:Chromatography, Ion Exchange / Q000379:methods*; D019343:Citric Acid / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D013058:Mass Spectrometry / Q000379:methods*; D011865:Radioisotope Dilution Technique; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012987:Soil / Q000032:analysis*; D012997:Solvents / Q000737:chemistry; D013696:Temperature; D013997:Time Factors
D002412:Cations; D012987:Soil; D012997:Solvents; D019343:Citric Acid; D000965:Antimony