Article

Conformal phased surfaces for wireless powering of bioelectronic microdevices

  • Nature Biomedical Engineering 1, Article number: 0043 (2017)
  • doi:10.1038/s41551-017-0043
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Abstract

Wireless powering could enable the long-term operation of advanced bioelectronic devices within the human body. Although both enhanced powering depth and device miniaturization can be achieved by shaping the field pattern within the body, existing electromagnetic structures do not provide the spatial phase control required to synthesize such patterns. Here, we describe the design and operation of conformal electromagnetic structures, termed phased surfaces, that interface with non-planar body surfaces and optimally modulate the phase response to enhance the performance of wireless powering. We demonstrate that the phased surfaces can wirelessly transfer energy across anatomically heterogeneous tissues in large animal models, powering miniaturized semiconductor devices (<12 mm3) deep within the body (>4 cm). As an illustration of in vivo operation, we wirelessly regulated cardiac rhythm by powering miniaturized stimulators at multiple endocardial sites in a porcine animal model.

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Acknowledgements

We acknowledge support from grants from the Singapore Institute for Neurotechnology, US National Science Foundation (ECCS-1351687), the US National Institutes of Health (National Institute of Biomedical Imaging and Bioengineering grant R21EB020894) and the Hong Kong Innovation and Technology Fund (ITS/087/14).

Author information

Affiliations

  1. Singapore Institute for Neurotechnology, National University of Singapore, Singapore 117456, Singapore

    • Devansh R. Agrawal
    • , Desen Weng
    •  & John S. Ho
  2. Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA

    • Yuji Tanabe
    • , Andrew Ma
    • , Stephanie Hsu
    •  & Ada S. Y. Poon
  3. Cardiology Division, Department of Medicine, University of Hong Kong, Hong Kong, China

    • Song-Yan Liao
    • , Zhe Zhen
    • , Zi-Yi Zhu
    •  & Hung Fat Tse
  4. Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583, Singapore

    • Chuanbowen Sun
    • , Zhenya Dong
    • , Fengyuan Yang
    •  & John S. Ho
  5. Hong Kong-Guangdong Joint Laboratory on Stem Cell and Regenerative Medicine, University of Hong Kong, Hong Kong, China.

    • Hung Fat Tse

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Contributions

H.F.T., A.S.Y.P. and J.S.H. jointly supervised this work. D.R.A., Y.T., D.W., A.M., S.H., C.S., Z.D., F.Y., A.S.Y.P. and J.S.H. built and characterized the wireless powering system. Y.T., A.M., S.H., S.-Y.L., Z.Z., Z.-Y.Z., H.F.T., A.S.Y.P. and J.S.H. performed the in vivo experiments. D.R.A., H.F.T., A.S.Y.P. and J.S.H. wrote the manuscript.

Competing interests

This work relates to patent PCT/US2015/052642.

Corresponding author

Correspondence to John S. Ho.

Supplementary information

PDF files

  1. 1.

    Supplementary Information

    Supplementary methods, figures and tables.

Videos

  1. 1.

    Supplementary Video 1

    Magnetic-field amplitude as the position of a bone structure is varied along the lateral direction (x direction, at z = 25 mm).

  2. 2.

    Supplementary Video 2

    Magnetic-field amplitude as the position of a bone structure is varied along the vertical direction (z direction, at x = 0 mm).

Text files

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    Supplementary code—sample data

    Sample data for the MATLAB scripts.

  2. 2.

    Supplementary code

    MATLAB scripts.