Impact of physical and chemical parameters on square wave anodic stripping voltammetry for trace Pb 2+ detection in water
Impact of physical and chemical parameters on square wave anodic stripping voltammetry for trace Pb 2+ detection in water
复制标题
理化参数对方波阳极溶出伏安法检测水中痕量Pb 2 的影响
DOI：
10.1039/d2an00724j
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Alvarez, Noe T.
中科院分区：
文献类型：
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作者：
Rahm, Connor E;Gupta, Pankaj;Gupta, Vandna K.;Huseinov, Artur;Griesmer, Ben;Alvarez, Noe T.
饮用水中的铅是一种有毒的重金属，是一个世界性的问题。铅从主要污染源铅供水管道和其他管道材料中的浸出受到水的铅溶解性的控制。方波阳极溶出伏安法（SWASV）是一种快速、简便的检测饮用水中痕量铅离子的方法。然而，水质参数（WQP）对SWASV技术的影响还没有得到很好的理解。在此，SWASV被用于检测10 μg L−1 Pb 2+，并确定模拟水样中溶出峰变化的趋势，同时单独改变pH值、电导率、碱度、游离氯、温度和铜水平。分别使用缓冲液3-（N-吗啉代）丙磺酸（MOPS）和NaNO 3控制pH值和电导率，并在探索其他WQP时保持pH = 7.0和电导率= 500 μS cm−1。工作电极是一种金纳米颗粒修饰的碳纳米管纤维横截面（AuNP-CNTf-CS）电极，对于10 μg L−1的Pb 2+检测提供了足够尖锐和突出的峰，以及良好的重现性，在模拟水中的相对误差为5.9%。我们发现，电导率，温度有一个正比关系的峰高，和pH值，碱度，游离氯，铜有一个反比关系。此外，增加铜的浓度引起的Pb 2+的溶出峰的加宽和移动。在极低的电导率（<100 μS cm−1）下，由于形成倒置和扭曲的峰，伏安图变得难以解释。然后，在当地饮用水样本中也观察到这些趋势，以验证结果。
Exposure to lead, a toxic heavy metal, in drinking water is a worldwide problem. Lead leaching from lead service lines, the main contamination source, and other plumbing materials is controlled by the plumbosolvency of water. Square wave anodic stripping voltammetry (SWASV) has been greatly explored as a rapid and portable technique for the detection of trace Pb2+ ions in drinking water. However, the impact of water quality parameters (WQP) on the SWASV technique is not well understood. Herein, SWASV was employed to detect 10 μg L−1 Pb2+ and determine trends in the stripping peak changes in simulated water samples while individually varying the pH, conductivity, alkalinity, free chlorine, temperature, and copper levels. The pH and conductivity were controlled using the buffer 3-(N-morpholino)propanesulfonic acid (MOPS), and NaNO3, respectively and kept at pH = 7.0 and conductivity = 500 μS cm−1 when exploring other WQPs. The working electrode, a gold-nanoparticle-modified carbon nanotube fiber cross-section (AuNP-CNTf-CS) electrode provided sufficiently sharp and prominent peaks for 10 μg L−1 Pb2+ detection as well as good reproducibility, with a relative error of 5.9% in simulated water. We found that conductivity, and temperature had a proportional relationship to the peak height, and pH, alkalinity, free chlorine, and copper had an inverse relationship. In addition, increasing the copper concentration caused broadening and shifting of the Pb2+ stripping peak. At extremely low conductivities (<100 μS cm−1), the voltammograms became difficult to interpret owing to the formation of inverted and distorted peaks. These trends were then also observed within a local drinking water sample in order to validate the results.