TY - JOUR
T1 - Skin-interfaced soft microfluidic systems with modular and reusable electronics for
T2 - In situ capacitive sensing of sweat loss, rate and conductivity
AU - Hourlier-Fargette, Aurélie
AU - Schon, Stéphanie
AU - Xue, Yeguang
AU - Avila, Raudel
AU - Li, Weihua
AU - Gao, Yiwei
AU - Liu, Claire
AU - Kim, Sung Bong
AU - Raj, Milan S.
AU - Fields, Kelsey B.
AU - Parsons, Blake V.
AU - Lee, Kunhyuck
AU - Lee, Jong Yoon
AU - Chung, Ha Uk
AU - Lee, Stephen P.
AU - Johnson, Michael
AU - Bandodkar, Amay J.
AU - Gutruf, Philipp
AU - Model, Jeffrey B.
AU - Aranyosi, Alexander J.
AU - Choi, Jungil
AU - Ray, Tyler R.
AU - Ghaffari, Roozbeh
AU - Huang, Yonggang
AU - Rogers, John A.
N1 - Funding Information:
This work utilized Northwestern University Micro/Nano Fabrication Facility (NUFAB), which is partially supported by Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205), the Materials Research Science and Engineering Center (DMR-1720139), the State of Illinois, and Northwestern University. The work was supported by the Querrey-Simpson Institute for Bioelectronics at Northwestern University. R. G., T. R. R. and A. J. A. acknowledge support from the National Institute on Aging of the National Institutes of Health (NIH R43AG067835). R. A. acknowledges support from the National Science Foundation Graduate Research Fellowship (NSF grant number 1842165) and Ford Foundation Predoctoral Fellowship. We thank 3M, Inc. for providing access to the 1524 adhesive used in this work.
PY - 2020/12/7
Y1 - 2020/12/7
N2 - Important insights into human health can be obtained through the non-invasive collection and detailed analysis of sweat, a biofluid that contains a wide range of essential biomarkers. Skin-interfaced microfluidic platforms, characterized by soft materials and thin geometries, offer a collection of capabilities for in situ capture, storage, and analysis of sweat and its constituents. In ambulatory uses cases, the ability to provide real-time feedback on sweat loss, rate and content, without visual inspection of the device, can be important. This paper introduces a low-profile skin-interfaced system that couples disposable microfluidic sampling devices with reusable 'stick-on' electrodes and wireless readout electronics that remain isolated from the sweat. An ultra-thin capping layer on the microfluidic platform permits high-sensitivity, contactless capacitive measurements of both sweat loss and sweat conductivity. This architecture avoids the potential for corrosion of the sensing components and eliminates the need for cleaning/sterilizing the electronics, thereby resulting in a cost-effective platform that is simple to use. Optimized electrode designs follow from a combination of extensive benchtop testing, analytical calculations and FEA simulations for two sensing configurations: (1) sweat rate and loss, and (2) sweat conductivity, which contains information about electrolyte content. Both configurations couple to a flexible, wireless electronics platform that digitizes and transmits information to Bluetooth-enabled devices. On-body field testing during physical exercise validates the performance of the system in scenarios of practical relevance to human health and performance. This journal is
AB - Important insights into human health can be obtained through the non-invasive collection and detailed analysis of sweat, a biofluid that contains a wide range of essential biomarkers. Skin-interfaced microfluidic platforms, characterized by soft materials and thin geometries, offer a collection of capabilities for in situ capture, storage, and analysis of sweat and its constituents. In ambulatory uses cases, the ability to provide real-time feedback on sweat loss, rate and content, without visual inspection of the device, can be important. This paper introduces a low-profile skin-interfaced system that couples disposable microfluidic sampling devices with reusable 'stick-on' electrodes and wireless readout electronics that remain isolated from the sweat. An ultra-thin capping layer on the microfluidic platform permits high-sensitivity, contactless capacitive measurements of both sweat loss and sweat conductivity. This architecture avoids the potential for corrosion of the sensing components and eliminates the need for cleaning/sterilizing the electronics, thereby resulting in a cost-effective platform that is simple to use. Optimized electrode designs follow from a combination of extensive benchtop testing, analytical calculations and FEA simulations for two sensing configurations: (1) sweat rate and loss, and (2) sweat conductivity, which contains information about electrolyte content. Both configurations couple to a flexible, wireless electronics platform that digitizes and transmits information to Bluetooth-enabled devices. On-body field testing during physical exercise validates the performance of the system in scenarios of practical relevance to human health and performance. This journal is
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U2 - 10.1039/d0lc00705f
DO - 10.1039/d0lc00705f
M3 - Article
C2 - 33089837
AN - SCOPUS:85096888147
VL - 20
SP - 4391
EP - 4403
JO - Lab on a Chip - Miniaturisation for Chemistry and Biology
JF - Lab on a Chip - Miniaturisation for Chemistry and Biology
SN - 1473-0197
IS - 23
ER -