Department of Civil and Environmental Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA.
Department of Electrical and Computer Engineering, University of Massachusetts Lowell, Lowell, MA, 01854, USA.
Mikrochim Acta. 2019 Oct 31;186(11):734. doi: 10.1007/s00604-019-3847-1.
This paper presents an electrochemical sensor for Cr(VI) (chromate ion) in water. A disposable screen-printed electrode was modified with gold nanostars (AuNSs) that were synthesized by Good's buffer method. Linear sweep voltammetry (LSV) was employed for the detection of Cr(VI) in 0.1 M sulfuric acid solution. The AuNSs are shown to provide higher current response to Cr(VI) than spherically shaped gold nanoparticles. The sensor gives the strongest response at a scan rate of 0.05 V (vs Ag/AgCl) and exhibits minimal interference from other electroactive species. The linear range extends from 10 to 75,000 ppb, and the limit of detection is 3.5 ppb. This is well below the provisional guideline value given by the World Health Organization. Excellent recoveries (ranging between 95 and 97%) were found when analyzing contaminated ground water samples obtained from a site situated in Wellesley, MA. Graphical abstract Schematic presentation of preparation of gold nanostars (AuNS) on carbon paste screen printed electrode (CPSPE) by drop casting and electrochemical detection of chromium (VI) using linear sweep voltammetry (LSV).
本文提出了一种用于水中六价铬（Cr(VI)）的电化学传感器。采用 Good 缓冲法合成的金纳米星（AuNSs）对一次性丝网印刷电极进行了修饰。在 0.1 M 硫酸溶液中，线性扫描伏安法（LSV）用于检测 Cr(VI)。结果表明，AuNSs 对 Cr(VI)的电流响应高于球形金纳米粒子。该传感器在扫描速率为 0.05 V（相对于 Ag/AgCl）时给出最强的响应，并表现出最小的其他电活性物质的干扰。线性范围从 10 到 75,000 ppb，检测限为 3.5 ppb。这远低于世界卫生组织给出的暂定指导值。在分析从马萨诸塞州威尔斯利的一个地点获得的受污染地下水样本时，发现回收率非常好（在 95%到 97%之间）。
