Department of Chemistry, Wayne State University, Detroit, Michigan 48202, United States.
Anal Chem. 2013 Aug 6;85(15):7535-41. doi: 10.1021/ac401539f. Epub 2013 Jul 10.
Lead (Pb) pollution is an important environmental and public health concern. Rapid Pb transport during stormwater runoff significantly impairs surface water quality. The ability to characterize and model Pb transport during these events is critical to mitigating its impact on the environment. However, Pb analysis is limited by the lack of analytical methods that can afford rapid, sensitive measurements in situ. While electrochemical methods have previously shown promise for rapid Pb analysis, they are currently limited in two ways. First, because of Pb's limited solubility, test solutions that are representative of environmental systems are not typically employed in laboratory characterizations. Second, concerns about traditional Hg electrode toxicity, stability, and low temporal resolution have dampened opportunities for in situ analyses with traditional electrochemical methods. In this paper, we describe two novel methodological advances that bypass these limitations. Using geochemical models, we first create an environmentally relevant test solution that can be used for electrochemical method development and characterization. Second, we develop a fast-scan cyclic voltammetry (FSCV) method for Pb detection on Hg-free carbon fiber microelectrodes. We assess the method's sensitivity and stability, taking into account Pb speciation, and utilize it to characterize rapid Pb fluctuations in real environmental samples. We thus present a novel real-time electrochemical tool for Pb analysis in both model and authentic environmental solutions.
铅（Pb）污染是一个重要的环境和公共卫生问题。暴雨径流期间快速的 Pb 迁移会严重影响地表水水质。描述和模拟这些事件中 Pb 迁移的能力对于减轻其对环境的影响至关重要。然而，Pb 分析受到缺乏能够在现场进行快速、灵敏测量的分析方法的限制。虽然电化学方法之前已经显示出快速 Pb 分析的潜力，但它们目前受到两种方式的限制。首先，由于 Pb 的溶解度有限，因此在实验室表征中通常不使用代表环境系统的测试溶液。其次，传统 Hg 电极毒性、稳定性和低时间分辨率的问题，抑制了传统电化学方法在现场分析中的应用。在本文中，我们描述了两种绕过这些限制的新方法学进展。我们首先使用地球化学模型创建一种环境相关的测试溶液，可用于电化学方法的开发和表征。其次，我们开发了一种在无 Hg 的碳纤维微电极上检测 Pb 的快速扫描循环伏安法（FSCV）方法。我们评估了该方法的灵敏度和稳定性，同时考虑了 Pb 的形态，并利用它来表征真实环境样品中快速的 Pb 波动。因此，我们提出了一种用于模型和真实环境溶液中 Pb 分析的新型实时电化学工具。
