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Title: Solid Contact Ion‐selective Electrodes on Printed Circuit Board with Membrane Displacement
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.  more » « less
Award ID(s):
1841509 1841473
PAR ID:
10390437
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Electroanalysis
Volume:
35
Issue:
1
ISSN:
1040-0397
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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