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We developed a potentiometric sensor system that includes a portable device and a multiplexed sensor based on solid-contact ion-selective electrodes (SCISE). SCISEs are fabricated using printed circuit board (PCB) and mesoporous carbon black (MCB) as the ion-to-electron transducer. The device supports sensor readout as well as automated sensor calibration, making it suitable for long term, in situ measurements.
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Design Criteria for Nanostructured Carbon Materials as Solid Contacts for Ion‐Selective Sensors
Abstract The ability to miniaturize ion‐selective sensors that enable microsensor arrays and wearable sensor patches for ion detection in environmental or biological samples requires all‐solid‐state sensors with solid contacts for transduction of an ion activity into an electrical signal. Nanostructured carbon materials function as effective solid contacts for this purpose. They can also contribute to improved potential signal stability, reducing the need for frequent sensor calibration. In this Perspective, the structural features of various carbon‐based solid contacts described in the literature and their respective abilities to reduce potential drift during long‐term, continuous measurements are compared. These carbon materials include nanoporous carbons with various architectures, carbon nanotubes, carbon black, graphene, and graphite‐based solid contacts. The effects of accessibility of ionophores, ionic sites, and other components of an ion‐selective membrane to the internal or external carbon surfaces are discussed, because this impacts double‐layer capacitance and potential drift. The effects of carbon composition on water‐layer formation are also considered, which is another contributor to potential drift during long‐term measurements. Recommendations regarding the selection of solid contacts and considerations for their characterization and testing in solid‐contact ion‐selective electrodes are provided.
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- Award ID(s):
- 2011401
- PAR ID:
- 10506834
- Publisher / Repository:
- Advanced Materials
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 36
- Issue:
- 8
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/adma.202309778
