汞硫属化物玻璃膜离子选择性电极在海水介质中的校准。

Calibration of the Hg chalcogenide glass membrane ion-selective electrode in seawater media.

作者信息

De Marco R, Shackleton J

机构信息

School of Applied Chemistry, Curtin University of Technology, GPO Box U 1987, Perth, WA 6845, Australia.

出版信息

Talanta. 1999 Jun 14;49(2):385-91. doi: 10.1016/s0039-9140(99)00003-x.

DOI:10.1016/s0039-9140(99)00003-x

PMID:18967611

Abstract

It is shown that a chalcogenide glass mercury(II) ion-selective electrode (ISE) can be calibrated in chloride-free unbuffered and saline buffered standards, displaying near-Nernstian response over 19 orders of magnitude (i.e. 10(-20) to 10(-1) M Hg(2+)). Extended ageing of the ISE in seawater induced a memory effect, causing the electrode to respond in a sub-Nernstian fashion. Electrochemical impedance spectroscopy (EIS) demonstrated that the response of the Hg(II) ISE is underpinned by a charge transfer process, and seawater matrix effects are due to electrode passivation. It is shown that standard addition ISE potentiometry may compensate for interferences caused by the seawater matrix.

摘要

结果表明，硫属化物玻璃汞（II）离子选择性电极（ISE）可在无氯、无缓冲和盐水缓冲的标准溶液中进行校准，在19个数量级（即10^(-20)至10^(-1) M Hg(2+)）范围内呈现近能斯特响应。ISE在海水中长时间老化会产生记忆效应，导致电极以亚能斯特方式响应。电化学阻抗谱（EIS）表明，Hg（II）ISE的响应是由电荷转移过程支撑的，海水基质效应是由于电极钝化所致。结果表明，标准加入ISE电位分析法可补偿海水基质引起的干扰。