Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), Université de Lorraine/CNRS, UMR7360, F54501 Vandœuvre-lès-Nancy, France.
Insight SFI Research Centre for Data Analytics, National Centre for Sensor Research, School of Chemical Sciences, Dublin City University, Dublin 9, Ireland.
Molecules. 2021 Sep 10;26(18):5502. doi: 10.3390/molecules26185502.
Electrochemical stripping techniques are interesting candidates for carrying out onsite speciation of environmentally relevant trace metals due to the existing low-cost portable instrumentation available and the low detection limits that can be achieved. In this work, we describe the initial analytical technique method development by quantifying the total metal concentrations using Stripping Chronopotentiometry (SCP). Carbon paste screen-printed electrodes were modified with thin films of mercury and used to quantify sub-nanomolar concentrations of lead and cadmium and sub-micromolar concentrations of zinc in river water. Low detection limits of 0.06 nM for Pb(II) and 0.04 nM for Cd(II) were obtained by the standard addition method using a SCP deposition time of 180 s. The SCP results obtained for Pb(II) and Cd(II) agreed with those of inductively coupled plasma mass spectrometry (ICP-MS). The coupling of SCP with screen-printed electrodes opens up excellent potential for the development of onsite speciation of trace metals. Due to the low analysis throughput obtained for the standard addition method, we also propose a new, more rapid screening Cd(II) internal standard methodology to significantly increase the number of samples that can be analyzed per day.
电化学剥离技术由于现有低成本便携式仪器和可达到的低检测限，是进行环境相关痕量金属现场形态分析的有吸引力的候选方法。在这项工作中，我们通过使用剥离计时电位法（SCP）定量测定总金属浓度来描述初始分析技术方法的开发。采用汞薄膜修饰的碳糊丝网印刷电极，用于定量测定河水中亚纳摩尔浓度的铅和镉，以及亚微米浓度的锌。通过使用 SCP 沉积时间为 180 s 的标准添加法，获得了 0.06 nM 的 Pb(II)和 0.04 nM 的 Cd(II)的低检测限。SCP 获得的 Pb(II)和 Cd(II)结果与电感耦合等离子体质谱法（ICP-MS）一致。SCP 与丝网印刷电极的结合为痕量金属的现场形态分析的发展开辟了极好的潜力。由于标准添加法获得的分析通量较低，我们还提出了一种新的、更快的 Cd(II)内标筛选方法，以显著增加每天可分析的样品数量。
