Paper-Based Potentiometric Ion Sensing
2014 (English)In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 86, no 19, 9548-9553 p.Article in journal, Letter (Refereed) Published
This paper describes the design and fabrication of ion-sensing electrochemical paper-based analytical devices (EPADs) in which a miniaturized paper reference electrode is integrated with a small ion-selective paper electrode (ISPE) for potentiometric measurements. Ion-sensing EPADs use printed wax barriers to define electrochemical sample and reference zones. Single-layer EPADs for sensing of chloride ions include wax-defined sample and reference zones that each incorporate a Ag/AgCl electrode. In EPADs developed for other electrolytes (potassium, sodium, and calcium ions), a PVC-based ion-selective membrane is added to separate the sample zone from a paper indicator electrode. After the addition of a small volume (less than 10 μL) of sample and reference solutions to different zones, ion-sensing EPADs exhibit a linear response, over 3 orders of magnitude, in ranges of electrolyte concentrations that are relevant to a variety of applications, with a slope close to the theoretical value (59.2/z mV). Ion-selective EPADs provide a portable, inexpensive, and disposable way of measuring concentrations of electrolyte ions in aqueous solutions.
Place, publisher, year, edition, pages
2014. Vol. 86, no 19, 9548-9553 p.
IdentifiersURN: urn:nbn:se:kth:diva-173687DOI: 10.1021/ac5018088ISI: 000343017100032OAI: oai:DiVA.org:kth-173687DiVA: diva2:855179
QC 201509212015-09-192015-09-162015-09-21Bibliographically approved