Marcellino Sébastien, Attar Hossein, Lièvremont Didier, Lett Marie-Claire, Barbier Frédérique, Lagarde Florence
Université de Lyon, Lyon1, Laboratoire des Sciences Analytiques, CNRS UMR 5180, bât CPE, 43, boulevard du 11 novembre 1918, 69622 Villeurbanne cédex, France.
Anal Chim Acta. 2008 Nov 23;629(1-2):73-83. doi: 10.1016/j.aca.2008.09.031. Epub 2008 Sep 18.
An analytical method was developed for antimony speciation and antimony(III) preconcentration in water samples. The method is based on the selective retention of Sb(III) by modified Saccharomyces cerevisiae in the presence of Sb(V). Heat, caustic and solvent pretreatments of the biomass were investigated to improve the kinetics and thermodynamics of Sb(III) uptake process at room temperature. Heating for 30 min at 80 degrees C was defined as the optimal treatment. Antimony accumulation by the cells was independent of pH (5-10) and ionic strength (0.01-0.1 mol L(-1)). 140 mg of yeast and 2h of contact were necessary to ensure quantitative sequestration of Sb(III) up to 750 microg L(-1). In these conditions, Sb(V) was not retained. Sb(V) was quantified in sorption supernatant by inductively coupled plasma mass spectrometry (ICP-MS) or inductively coupled plasma optical emission spectrometry (ICP-OES). Sb(III) was determined after elution with 40 mmol L(-1) thioglycolic acid at pH 10. A preconcentration factor close to nine was achieved for Sb(III) when 100mL of sample was processed. After preconcentration, the detection limits for Sb(III) and Sb(V) were 2 and 5 ng L(-1), respectively, using ICP-MS, 7 and 0.9 microg L(-1) using ICP-OES. The proposed method was successfully applied to the determination of Sb(III) and Sb(V) in spiked river and mineral water samples. The relative standard deviations (n=3) were in the 2-5% range at the tenth microg L(-1) level and less than 10% at the lowest Sb(III) and Sb(V) tested concentration (0.1 microg L(-1)). Corrected recoveries were in all cases close to 100%.
开发了一种用于水样中锑形态分析和锑（III）预富集的分析方法。该方法基于在锑（V）存在下，经改性的酿酒酵母对锑（III）的选择性保留。研究了生物质的加热、碱处理和溶剂预处理，以改善室温下锑（III）吸收过程的动力学和热力学。将在80℃加热30分钟定义为最佳处理。细胞对锑的积累与pH值（5 - 10）和离子强度（0.01 - 0.1 mol L(-1)）无关。需要140 mg酵母和2小时的接触时间，以确保对高达750 μg L(-1)的锑（III）进行定量螯合。在这些条件下，锑（V）不被保留。通过电感耦合等离子体质谱（ICP-MS）或电感耦合等离子体发射光谱（ICP-OES）对吸附上清液中的锑（V）进行定量。用40 mmol L(-1)巯基乙酸在pH 10下洗脱后测定锑（III）。当处理100 mL样品时，锑（III）的预富集因子接近9。预富集后，使用ICP-MS时，锑（III）和锑（V）的检测限分别为2和5 ng L(-1)，使用ICP-OES时分别为7和0.9 μg L(-1)。所提出的方法成功应用于加标河水和矿泉水样品中锑（III）和锑（V）的测定。在第十微克每升水平下，相对标准偏差（n = 3）在2 - 5%范围内，在测试的最低锑（III）和锑（V）浓度（0.1 μg L(-1)）下小于10%。所有情况下校正回收率均接近100%。
