Potentiometric probes used in direct potentiometry are attractive sensing tools. They give information on ion activities, which is often uniquely useful. If, instead, concentrations are desired as sensor output, the ionic strength of the sample must be precisely known, which is often not possible. Here, for the first time, direct potentiometry can be made to report concentrations, rather than activities. It is demonstrated for the detection of monovalent anionic species by using a self-referencing Ag/AgI pulstrode as the reference element instead of a traditional reference electrode. This reference pulstrode releases a discrete quantity of iodide ions from the electrode and the resulting reference potential varies with the activity coefficient of iodide. The effects of activity coefficient on the indicator and reference electrode are therefore compensated and the observed cell potential may now be described in a Nernstian manner against anion concentration, rather than activity. Theoretical simulations and experimental results support the validity of this approach. For most monovalent anions of practical relevance, the potential difference between this approach and from a traditional activity coefficient calculation is less than 0.5 mV. The concept is validated with an all-solid-state nitrate sensor as well as a commercial fluoride-selective electrode, giving Nernstian responses in different ionic strength backgrounds against concentration without the need for correcting activity coefficients or liquid junction potentials.

Wenyue Gao

Xiaojiang Xie

Eric Bakker

ACS Sensors

ACS SENSORS 是一份经过同行评审的研究期刊，致力于传播有关选择性感知化学或生物物种或过程的传感器科学各个方面的新知识和原创知识。文章可能涉及适用于多种类型分析物的传感概念进展，或报告以新方式或新分析物使用现有传感概念的应用论文。申请文件应展示传感器在复杂样品中的使用，证明其适用，并展示传感器性能与现有分析方法的相关性。论文可能侧重于传感器的商业化开发或开发用于提供新科学知识的传感器。文章可能完全是关于传感的理论，也可能报告实验结果。

ACS SENSORS is a peer-reviewed research journal dedicated to disseminating new and original knowledge in all aspects of sensor science related to the selective detection of chemical or biological species or processes. Articles may cover advancements in sensing concepts applicable to various analytes or report applications of existing sensing concepts using new approaches or analytes. Submitted manuscripts should demonstrate the use of sensors in complex samples, establish their applicability, and relate sensor performance to existing analytical methods. Papers may focus on the commercialization of sensors or the development of sensors aimed at providing new scientific insights. Articles may be purely theoretical regarding sensing or may report experimental results.

ACS SENSORS 是一本经过同行评审的研究期刊，专注于传播关于选择性感知化学或生物物种及其过程的传感器科学的最新研究成果和原创性知识。文章可能涉及适用于多种类型分析物的传感概念的进展，或报告以新方式或新分析物使用现有传感概念的应用研究。提交的论文应展示传感器在复杂样品中的应用，证明其适用性，并展示传感器性能与现有分析方法之间的相关性。论文可以专注于传感器的商业化开发，或开发用于提供新科学知识的传感器。文章内容可能完全是关于传感的理论研究，也可能报告实验结果。

Direct Potentiometric Sensing of Anion Concentration (Not Activity)

Direct potentiometry can be made to report concentrations, rather than activities, for the first time, with an all-solid-state nitrate sensor as well as a commercial fluoride-selective electrode, giving nernstian responses in different ionic strength backgrounds against concentration without the need for correcting activity coefficients or liquid junction potentials.

Category	Quartile
化学	1
化学, 分析化学	1
化学, 化学综合	2
化学, 纳米科技	2

Direct Potentiometric Sensing of Anion Concentration (Not Activity)

ivySCI AI Smartly Parses PDF, Answers Researchers' Questions, and Helps You Understand Papers in Seconds

Journal Info

Category	Quartile
NANOSCIENCE & NANOTECHNOLOGY	1