Universidade Federal da Bahia, Instituto de Química, Grupo de Pesquisa em Química e Quimiometria, CEP 40170-270 Salvador, Bahia, Brazil; Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n, 15782 Santiago de Compostela, Spain; Universidade Federal da Bahia, Faculdade de Medicina da Bahia, CEP 40025-010 Salvador, Bahia, Brazil.
Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, University of Santiago de Compostela, Avenida das Ciencias, s/n, 15782 Santiago de Compostela, Spain.
Talanta. 2017 Aug 1;170:523-529. doi: 10.1016/j.talanta.2017.04.034. Epub 2017 Apr 20.
This work proposes the use of high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for simultaneous speciation of arsenic and chromium in iron supplements used for the treatment of anemia. The sample preparation procedure recommended for the total determination of arsenic and chromium was established using acid digestion in a microwave assisted oven. For speciation analysis, however, the microwave-assisted extraction procedure involved the use of water as extraction solvent at 90°C for 30min. The chromatographic separation was performed using a mobile phase containing 1.0mM tetrabutylammonium hydroxide (TBAH), 0.7mM ethylenediaminetetraacetic acid (EDTA) and 5% methanol at pH 7.2. Helium was used in the collision cell for elimination of the interferences. Under optimized conditions, the separation and detection of the As(III), As(V), Cr(III) and Cr(VI) species can be performed in 5min, permitting their quantification with the external calibration technique with standards prepared in the mobile phase. The limits of quantification obtained were 0.008, 0.010, 0.5 and 0.14µgg, for As(III), As(V), Cr(III) and Cr(VI), respectively. The accuracy of the method was evaluated and confirmed by addition/recovery tests. The recoveries obtained varied from 81% to 110%. The proposed method was applied to the speciation analysis of arsenic and chromium in commercially available iron supplements acquired in several cities in Brazil and Spain. The content of the species ranged from 0.01 to 1.3µgg for arsenic, and from 0.4 to 61.2µgg for chromium.
本工作提出了使用高效液相色谱与电感耦合等离子体质谱联用（HPLC-ICP-MS）同时对用于治疗贫血的铁补充剂中的砷和铬进行形态分析。为了进行总砷和总铬的测定，推荐使用微波辅助酸消解进行样品前处理。然而，对于形态分析，微波辅助萃取程序采用水作为提取溶剂，在 90°C 下提取 30min。采用含有 1.0mM 四丁基氢氧化铵（TBAH）、0.7mM 乙二胺四乙酸（EDTA）和 5%甲醇的流动相进行色谱分离，在 pH 7.2 下进行。氦气在碰撞池中用于消除干扰。在优化条件下，可以在 5min 内分离和检测 As(III)、As(V)、Cr(III)和 Cr(VI)形态，允许使用在流动相制备的标准品进行外部校准技术进行定量。获得的定量下限分别为 0.008、0.010、0.5 和 0.14µgg，用于 As(III)、As(V)、Cr(III)和 Cr(VI)。通过添加/回收测试评估和验证了方法的准确性。获得的回收率在 81%至 110%之间变化。该方法应用于从巴西和西班牙几个城市购买的市售铁补充剂中砷和铬的形态分析。各形态的含量范围为 0.01 至 1.3µgg 之间的砷，以及 0.4 至 61.2µgg 之间的铬。
