Dos Anjos Vanessa E, Abate Gilberto, Grassi Marco T
Departamento de Química, Universidade Federal do Paraná (UFPR), CP 19032, Centro Politécnico Jardim das Américas, Curitiba, Paraná, 81531-980, Brazil.
Departamento de Química, Universidade Estadual de Ponta Grossa (UEPG), Avenida Carlos Cavalcanti 4748, Ponta Grossa, Paraná, 84030-900, Brazil.
Anal Bioanal Chem. 2017 Mar;409(7):1963-1972. doi: 10.1007/s00216-016-0144-2. Epub 2016 Dec 22.
A binding phase based on the clay mineral montmorillonite (MT) was used as a sorbent in this work, which employed diffusive gradients in thin-film (DGT) devices to determine the lability of trace elements in natural waters. Montmorillonite exhibits low cost, wide availability, ease of handling, high ion-exchange capacity, and reusability. As(V), Ba, Cd, Co, Cr(III), Cu, Mn, Ni, Pb, Sr, V(V), and Zn were quantitatively sorbed by MT and eluted with 1.0 mol L HNO, which provided efficiency above 70% of recovery. Validation tests were performed with synthetic solutions. The recovery of known concentrations ranged from 83 to 110%. The performance of modified DGT was compared with conventional DGT devices in experiments lasting 6 and 48 h. The results obtained with both DGT devices showed no significant differences with 95% confidence. DGT samplers with MT were deployed in the determination of labile forms of the elements in water samples from Iguaçu River (Paraná, Brazil). The measured masses of elements in MT for various durations showed good fit to a theoretical line, indicating that the results agreed with the principle of the DGT technique. The concentrations of labile species in the sample proceeded as follows; Sr > Cd > Ba > Cu > Cr > Mn > Zn > Pb. The results suggest that DGT devices with MT are an effective alternative for speciation analysis of a wide range of elements (cations as well as anions) in natural waters.
在本研究中，基于粘土矿物蒙脱石（MT）的结合相被用作吸附剂，采用薄膜扩散梯度（DGT）装置来测定天然水体中微量元素的活性。蒙脱石具有成本低、来源广泛、易于处理、离子交换容量高和可重复使用等优点。MT能定量吸附砷（V）、钡、镉、钴、铬（III）、铜、锰、镍、铅、锶、钒（V）和锌，并用1.0 mol/L硝酸洗脱，回收率高于70%。用合成溶液进行了验证试验。已知浓度的回收率在83%至110%之间。在持续6小时和48小时的实验中，将改良DGT的性能与传统DGT装置进行了比较。两种DGT装置获得的结果在95%置信度下无显著差异。装有MT的DGT采样器被用于测定巴西巴拉那州伊瓜苏河河水样品中元素的活性形态。不同时间段MT中元素的测量质量与理论曲线拟合良好，表明结果符合DGT技术原理。样品中活性物种的浓度顺序如下：锶>镉>钡>铜>铬>锰>锌>铅。结果表明，装有MT的DGT装置是天然水体中多种元素（阳离子和阴离子）形态分析的有效替代方法。
