图片来源：Metrohm AG
本文重点介绍了Sctrace Gold电极，特别是在“重金属”分析中使用。金电极已用于电化学多年了，但是Sctrace Gold利用了非常特殊的设计。
While it was initially developed to enhance the voltammetric determination of arsenic, the electrode has demonstrated suitability for the determination of a number of other elements including lead, iron, copper, and even the toxic chromium(VI).
How Does the scTRACE Gold Electrode Work?
这working electrode is comprised of a gold micro-wire (Figure 1), a wire thinner than a human hair. This special type of electrode offers a very short initial preparation time, with thescTRACE Gold准备在几分钟内使用。
Figure 1.Sctrace Gold上金微线工作电极的特写景观。图片来源：Metrohm AG
该电极包括传感器后侧的参考和辅助电极（图2）。这不仅可以节省伏安系统中两个额外的，必要的电极的成本，还可以消除维护参考电极的任何需求。
图2。Close-up view of the reference and auxiliary electrode on the rear side of the scTRACE Gold. Image Credit: Metrohm AG
申请
Voltammetry’s high sensitivity and simple setup make it a valuable tool in drinking water analysis.
Ensuring that clean drinking water is available to all is one of the main concerns of the 21英石世纪。除了微生物污染（例如，病毒和细菌），饮用水中的重金属存在可能带来重大的健康风险。
这provision of clean water requires an accurate identification of contaminants. Health-threatening concentrations of heavy metals are not immediately visible, so limit values of these heavy metals in drinking water are stipulated by authorities like the European Commission and the U.S. Environmental Protection Agency (EPA).
Water quality laboratories often make use of ICP (inductively coupled plasma) to monitor the concentration of metals in drinking water, but voltammetry is one of a handful of analysis techniques offering a comparable level of sensitivity.
因为它仅需要基本的基础架构并提供较低的运行成本，因此伏安法是监视某些关键元素的实用替代方法。以下各节概述了一系列选定的应用示例，证明了Sctrace Gold Electrode的水分析功能。
Arsenic in Drinking Water
Arsenic gained a degree of global notoriety when water wells were constructed in Bangladesh with a view to avoiding diseases caused by microbiological contaminations in surface water. When the wells were built, however, people became afflicted with chronic arsenic poisoning rather than suffering from cholera or hepatitis.
图片来源：Metrohm AG
天真地假设砷在较不发达国家只是一个问题，因为砷几乎在地壳中几乎到处都是。
砷的浓度使其有毒，因此关键问题是围绕着多少砷可以进入地下水位。世界卫生组织建议在任何用于人类消费的水中最大浓度为10 µg/l砷 - 这也是几个国家的法定限制。
10 µg/l的极限值的伏安确定显示，回收约为92％（n = 10个测定），相对标准偏差为6.5％。使用Sctrace Gold电极的伏安法的检测极限为1 µg/L-法定限制的十分之一。它提供了一种经济高效，可靠的方法来监测饮用水的砷含量。
这Sctrace金电极can be used with the 946 Portable VA Analyzer and the 884 Professional VA; the former being intended for mobile use and onsite determination, and the latter being designed for laboratory use.
该系统非常灵活，可以轻松适应以满足特定的用户需求。该仪器的模块化设置还可以根据需要将其从手动使用升级到完全自动化。
图片来源：Metrohm AG
铜在地表水中
在正常情况下，饮用水中的铜无需担心。法律限制相对较高，谁建议最高浓度为2 mg/L。然而，田间的示例显示了谨慎地确定水中铜的实例。
图片来源：Metrohm AG
杜松子酒，白兰地，威士忌和施纳普等蒸馏酒精饮料的生产涉及原材料的单次甚至多次蒸馏。这是在铜蒸馏器中完成的，清理这些铜设备并将冲洗水排入河流的过程可能会导致环境被铜污染。
Regulatory limits for effluents are generally higher than those for drinking water, but copper limits may still be exceeded if the water is not properly treated before it is discharged. Pollution from these cleaning processes only occurs periodically, making it challenging to detect and even more difficult to confirm, particularly in less accessible areas.
Mobile voltammetry using the scTRACE Gold alongside the946便携式VA分析仪可以在这里做出宝贵的贡献，通过有效确定低浓度的铜来帮助保护环境。
对于5 µg/L的浓度，10个测定的平均恢复约为107％，相对标准偏差为2％。低至0.5 µg/l铜的浓度可以直接在水中采样点上确定。
Immediate re-sampling can be performed where results may be suspicious, further helping to locate the source of the pollution. Increased chances of identifying the source increase the chance of successfully holding the culprit accountable.
饮用水
根据世界卫生组织的说法，铁在饮用水中通常发现的水平没有任何健康问题。铁也是人类营养的重要元素。无论如何，许多国家/地区规定在200 µg/L和300 µg/L之间的最大污染物水平，因为较高浓度的铁将对水的味道产生不利影响，并且可能会染色和卫生。电器。
图片来源：Metrohm AG
伏安确定铁的检测极限为10 µg/L有助于促进一种简单的方法来监测任何供水中的铁浓度。伏安测定20 µg/L Fe的恢复在91％（n = 10个测定）范围内，相对标准偏差为1％。
致谢
由最初由Metrohm Ba亚博网站下载rbaraZumbrägel撰写的材料生产。
This information has been sourced, reviewed and adapted from materials provided by Metrohm AG.
有关此消息来源的更多信息，请访问Metrohm Ag。