Simultaneous Separation of Sb(III) and Sb(V) by High Performance Liquid Chromatography (HPLC) – Inductively Coupled Plasma – Mass Spectrometry (ICP-MS) with Application to Plants, Soils, and Sediments

The simultaneous separation and determination of inorganic trivalent antimony Sb(III) and pentavalent antimony Sb(V) in plant, soil, and sediment samples was carried out by high performance liquid chromatography – inductively coupled plasma – mass spectrometry (HPLC-ICP-MS). The chromatographic conditions (composition and concentration of competing ion, pH value and flow rate of mobile phase) and the operating parameters for inductively coupled plasma – mass spectrometry were optimized by single factor experiments. The separation of the Sb species was achieved within 6 min using the optimized chromatographic conditions. The detection limits of the method were 0.016 μg/L and 0.021 μg/L for Sb(III) and Sb(V), respectively. The retention times of Sb(V) and Sb(III) were 2.7 min and 4.5 min, respectively. The relative standard deviations for replicate measurements (n = 6) of low (5 μg/L), medium (20 μg/L), and high (40 μg/L) concentrations of Sb(III) and Sb(V) were less than 4%. The results of spiking and recovery experiments for the extracting solutions of soil, sediments, and plants showed that the spiked recoveries of the two species ranged from 92% to 103%. This method has been used to determine the antimony species in extracts of environmental samples.