Department of Chemistry, Karaj Branch, Islamic Azad University, Karaj, Iran.
Department of Chemistry, Karaj Branch, Islamic Azad University, Karaj, Iran.
Talanta. 2022 Feb 1;238(Pt 1):123031. doi: 10.1016/j.talanta.2021.123031. Epub 2021 Nov 2.
In this work, gel electro-membrane extraction (G-EME) combined with flame atomic absorption spectrometry (FAAS) was used for the determination of zinc ions (Zn) in water samples. For the first time, the effect of the presence of three types of complexing agents such as phenanthroline (Phen), crown ethers (12C4, 15C5, 18C6), and ethylene-diamine-tetra-acetic acid (EDTA) on the extraction efficiency of zinc ions was studied. In addition, the electroendosmosis (EEO) flow as an unwanted actuator was monitored in the presence and absence of complexing agents. By applying 50 V electrical potential across the membrane, the positive charged Zn ions were migrated from a donor phase (pH 5.0) through the agarose gel membrane (pH 5.0, containing a complexing agent) into the acceptor phase (pH 3.0). The obtained results showed that the highest extraction recoveries were obtained when crown ethers, especially 1% (w/v) 18C6 was added to the gel membrane. In addition, EEO flow was decreased in the presence of all complexing agents (except EDTA), probably due to the increase in electrical resistance. Using the optimum conditions, the limit of detection (LOD), the limit of quantification (LOQ), and extraction recovery% (ER%) were 5.0 μg L, 15.0 μg L and 92.5%, respectively. In the end, the applicability of the developed approach was successfully evaluated to determine Zn in tap, mineral, and river water samples.
在这项工作中，凝胶电膜萃取（G-EME）与火焰原子吸收光谱法（FAAS）相结合，用于测定水样中的锌离子（Zn）。首次研究了三种络合剂，如邻菲啰啉（Phen）、冠醚（12C4、15C5、18C6）和乙二胺四乙酸（EDTA）的存在对锌离子萃取效率的影响。此外，监测了电渗流（EEO）作为一种不需要的致动器在存在和不存在络合剂时的情况。通过在膜两端施加 50V 的电势，带正电荷的 Zn 离子从供体相（pH5.0）通过琼脂糖凝胶膜（pH5.0，含有络合剂）迁移到受体相（pH3.0）。结果表明，当凝胶膜中加入冠醚（尤其是 1%（w/v）18C6）时，可获得最高的萃取回收率。此外，所有络合剂（除 EDTA 外）的存在都降低了 EEO 流，这可能是由于电阻增加所致。在最佳条件下，检测限（LOD）、定量限（LOQ）和萃取回收率（ER%）分别为 5.0μg L、15.0μg L 和 92.5%。最后，成功评估了该方法在测定自来水中、矿泉水和河水中的 Zn 的适用性。
