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Abstract Multiplexed solid‐contact ion‐selective electrodes (SCISEs) are fabricated using printed circuit board (PCB) and mesoporous carbon black (MCB) as ion‐to‐electron transducer (solid contact). Four sensor configurations were examined and showed that in addition to MCB, the sensor configuration plays crucial role in the stability of the potential response. The enhanced sensor stability was also linked with suppression of transmembrane flux of water. The sensors exhibited near‐Nernstian sensitivity (58.1 mV/dec for K+ISEs and −55.1 mV/dec for NO3‐ISEs), low detection limits (1.5–2.2 μM), and good short‐term stability (∼0.1 mV/min). Sensors can be stored dry and used without preconditioning. This work demonstrates a promising approach to combining PCB technology and carbon black for large‐scale production of low cost ISEs for point‐of‐care testing, wearables, orin situfield measurements.
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Multiplex Sensor for Ion Sensing Based on Printed Circuit Board
We fabricated and evaluated multiplexed ion-selective electrodes (ISEs) by modifying printed circuit board (PCB). The multiplexed sensor consisted of all-solid-state K+ and NO3- ISEs, together with a Ag/AgCl reference. The sensor was further embedded in a microfluidic microchannel for in-line continuous analysis, and was characterized for up to one week of operation. Both ISEs showed a near-Nernstian response (~52 mV/dec) and reasonable stabilities (baseline drift ~2.9 mV/day). The sensor provides a versatile and low-cost tool for monitoring concentrations of different ions in many biomedical, environmental and agricultural applications.
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- Award ID(s):
- 1841509
- PAR ID:
- 10210816
- Date Published:
- Journal Name:
- 24th International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2020)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Conference Paper:
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