Development of Miniature Solid Contact Ion Selective Electrodes for in situ Instrumentation

Abstract

AbstractUsing a standardized miniature format ion selective electrode, five different carbon based solid contact materials, including a novel commercially available graphene oxide assisted carbon nanotube dispersion (FlexipheneTM), were compared. The electromotive force (EMF) response, stability, and behavior following storage was evaluated. Bulk resistance for the novel graphene oxide/carbon nanotube (GO‐CNT) based ISE was observed to be 0.09±0.03 MΩ, which is two orders of magnitude lower than reported for either component in isolation. The results for previously described solid contact materials are in general agreement with the literature, and the tradeoffs between solid contact layer material choices are discussed. Performance of GO‐CNT solid contact ion selective electrodes were then evaluated in a 3D‐printed fluidic array to determine their suitability for future in situ instruments.