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Title: Wireless Detection of Trace Ammonia: A Chronic Kidney Disease Biomarker
Elevated levels of ammonia in breath can be linked to medical complications such as chronic kidney disease (CKD) that disturb the urea balance in the body. However, early-stage CKD is usually asymptomatic and mass screening is hindered by high instrumentation and operation requirements, accessible and reliable detection methods for CKD biomarkers, such as trace ammonia in breath. Enabling methods would have significance in population screening for early-stage CKD patients. We herein report a method to effectively immobilize transition metal selectors in close proximity to single-walled carbon nanotube (SWCNT) surface using pentiptycene polymers containing metal-chelating backbone structures. The robust and modular nature of the pentiptycene metallopolymer/SWCNT complexes create a platform that accelerates sensor discovery and optimization. Using these methods, we have identified sensitive, selective, and robust copper-based chemiresistive ammonia sensors displaying low parts per billion detection limits. We have added these hybrid materials into the resonant radio frequency circuits of commercial near-field communication (NFC) tags to achieve robust wireless detection of ammonia at physiologically relevant levels. The integrated devices offer a non-invasive and cost-effective approach for early detection and monitoring of CKD.  more » « less
Award ID(s):
2207299
PAR ID:
10517321
Author(s) / Creator(s):
;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
ACS Nano
Volume:
18
Issue:
1
ISSN:
1936-0851
Page Range / eLocation ID:
364 to 372
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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