Letter | Published:

Fully integrated wearable sensor arrays for multiplexed in situ perspiration analysis

Nature volume 529, pages 509514 (28 January 2016) | Download Citation

Abstract

Wearable sensor technologies are essential to the realization of personalized medicine through continuously monitoring an individual’s state of health1,2,3,4,5,6,7,8,9,10,11,12. Sampling human sweat, which is rich in physiological information13, could enable non-invasive monitoring. Previously reported sweat-based and other non-invasive biosensors either can only monitor a single analyte at a time or lack on-site signal processing circuitry and sensor calibration mechanisms for accurate analysis of the physiological state14,15,16,17,18. Given the complexity of sweat secretion, simultaneous and multiplexed screening of target biomarkers is critical and requires full system integration to ensure the accuracy of measurements. Here we present a mechanically flexible and fully integrated (that is, no external analysis is needed) sensor array for multiplexed in situ perspiration analysis, which simultaneously and selectively measures sweat metabolites (such as glucose and lactate) and electrolytes (such as sodium and potassium ions), as well as the skin temperature (to calibrate the response of the sensors). Our work bridges the technological gap between signal transduction, conditioning (amplification and filtering), processing and wireless transmission in wearable biosensors by merging plastic-based sensors that interface with the skin with silicon integrated circuits consolidated on a flexible circuit board for complex signal processing. This application could not have been realized using either of these technologies alone owing to their respective inherent limitations. The wearable system is used to measure the detailed sweat profile of human subjects engaged in prolonged indoor and outdoor physical activities, and to make a real-time assessment of the physiological state of the subjects. This platform enables a wide range of personalized diagnostic and physiological monitoring applications.

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Acknowledgements

The sensor design, characterization and testing aspects of this work were supported by the Berkeley Sensor and Actuator Center, and National Institutes of Health grant number 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 US Department of Energy under contract number DE-AC02-05CH11231. K.C. acknowledges funding from the NSF Nanomanufacturing Systems for mobile Computing and Energy Technologies (NASCENT) Center. H.O. acknowledges support from a Japan Society for the Promotion of Science (JSPS) Fellowship. We thank J. Bullock, C. M. Sutter-Fella, H. W. W. Nyein, Z. Shahpar, M. Zhou, E. Wu and W. Chen for their help.

Author information

Author notes

    • Wei Gao
    •  & Sam Emaminejad

    These authors contributed equally to this work.

Affiliations

  1. Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA

    • Wei Gao
    • , Sam Emaminejad
    • , Hnin Yin Yin Nyein
    • , Kevin Chen
    • , Hossain M. Fahad
    • , Hiroki Ota
    • , Hiroshi Shiraki
    • , Daisuke Kiriya
    • , Der-Hsien Lien
    •  & Ali Javey
  2. Berkeley Sensor and Actuator Center, University of California, Berkeley, California 94720, USA

    • Wei Gao
    • , Sam Emaminejad
    • , Hnin Yin Yin Nyein
    • , Kevin Chen
    • , Hossain M. Fahad
    • , Hiroki Ota
    • , Hiroshi Shiraki
    • , Daisuke Kiriya
    • , Der-Hsien Lien
    •  & Ali Javey
  3. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA

    • Wei Gao
    • , Sam Emaminejad
    • , Hnin Yin Yin Nyein
    • , Kevin Chen
    • , Hossain M. Fahad
    • , Hiroki Ota
    • , Hiroshi Shiraki
    • , Daisuke Kiriya
    • , Der-Hsien Lien
    •  & Ali Javey
  4. Stanford Genome Technology Center, Stanford School of Medicine, Palo Alto, California 94304, USA

    • Sam Emaminejad
    • , Samyuktha Challa
    •  & Ronald W. Davis
  5. Integrative Biology, University of California, Berkeley, California 94720, USA

    • Austin Peck
    •  & George A. Brooks

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Contributions

W.G., S.E. and A.J. conceived the idea and designed the experiments. W.G., S.E., H.Y.Y.N. and S.C. led the experiments (with assistance from K.C., A.P., H.M.F., H.O., H.S., H.O., D.K., D.-H.L.). W.G., S.E., A.P., G.A.B., R.W.D. and A.J. contributed to data analysis and interpretation. W.G., S.E., H.Y.Y.N., G.A.B. and A.J. wrote the paper and all authors provided feedback.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Ali Javey.

Extended data

Supplementary information

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    Supplementary Information

    This file contains Supplementary Table 1, Supplementary Discussions for selection of the target analytes and Supplementary References.

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DOI

https://doi.org/10.1038/nature16521

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