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A Wearable Electrochemical Platform for Noninvasive Simultaneous Monitoring of Ca^(2+) and pH

Nyein, Hnin Yin Yin and Gao, Wei and Shahpar, Ziba and Emaminejad, Sam and Challa, Samyuktha and Chen, Kevin and Fahad, Hossain M. and Tai, Li-Chia and Ota, Hiroki and Davis, Ronald W. and Javey, Ali (2016) A Wearable Electrochemical Platform for Noninvasive Simultaneous Monitoring of Ca^(2+) and pH. ACS Nano, 10 (7). pp. 7216-7224. ISSN 1936-0851.

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Homeostasis of ionized calcium in biofluids is critical for human biological functions and organ systems. Measurement of ionized calcium for clinical applications is not easily accessible due to its strict procedures and dependence on pH. pH balance in body fluids greatly affects metabolic reactions and biological transport systems. Here, we demonstrate a wearable electrochemical device for continuous monitoring of ionized calcium and pH of body fluids using a disposable and flexible array of Ca^(2+) and pH sensors that interfaces with a flexible printed circuit board. This platform enables real-time quantitative analysis of these sensing elements in body fluids such as sweat, urine, and tears. Accuracy of Ca^(2+) concentration and pH measured by the wearable sensors is validated through inductively coupled plasma-mass spectrometry technique and a commercial pH meter, respectively. Our results show that the wearable sensors have high repeatability and selectivity to the target ions. Real-time on-body assessment of sweat is also performed, and our results indicate that calcium concentration increases with decreasing pH. This platform can be used in noninvasive continuous analysis of ionized calcium and pH in body fluids for disease diagnosis such as primary hyperparathyroidism and kidney stones.

Item Type:Article
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URLURL TypeDescription ItemSupporting Information
Gao, Wei0000-0002-8503-4562
Chen, Kevin0000-0002-6726-6132
Javey, Ali0000-0001-7214-7931
Additional Information:© 2016 American Chemical Society. Received 16 June 2016. Date accepted 5 July 2016. Published online 5 July 2016. Published in print 26 July 2016. This work at the University of California, Berkeley was supported by NSF Nanomanufacturing Systems for Mobile Computing and Energy Technologies (NASCENT) Center and at Stanford University was supported by the National Institutes of Health grant no. P01 HG000205. The sensor fabrication was performed in the Electronic Materials (E-MAT) laboratory funded by the Director, Office of Science, Office of Basic Energy Sciences, Material Sciences and Engineering Division of the U.S. Department of Energy under contract no. DE-AC02-05CH11231. K.C. acknowledges support from the Robert N. Noyce Fellowship in Microelectronics. The authors thank H.W.W.N. for her assistance.
Funding AgencyGrant Number
NIHP01 HG000205
Department of Energy (DOE)DE-AC02-05CH11231
Robert N. Noyce FellowshipUNSPECIFIED
Issue or Number:7
Record Number:CaltechAUTHORS:20170922-092448300
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Official Citation:A Wearable Electrochemical Platform for Noninvasive Simultaneous Monitoring of Ca2+ and pH Hnin Yin Yin Nyein, Wei Gao, Ziba Shahpar, Sam Emaminejad, Samyuktha Challa, Kevin Chen, Hossain M. Fahad, Li-Chia Tai, Hiroki Ota, Ronald W. Davis, and Ali Javey ACS Nano 2016 10 (7), 7216-7224 DOI: 10.1021/acsnano.6b04005
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:81736
Deposited By: Ruth Sustaita
Deposited On:22 Sep 2017 16:38
Last Modified:09 Mar 2020 13:18

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