Letter | Published:

Wireless bioresorbable electronic system enables sustained nonpharmacological neuroregenerative therapy


Peripheral nerve injuries represent a significant problem in public health, constituting 2–5% of all trauma cases1. For severe nerve injuries, even advanced forms of clinical intervention often lead to incomplete and unsatisfactory motor and/or sensory function2. Numerous studies report the potential of pharmacological approaches (for example, growth factors, immunosuppressants) to accelerate and enhance nerve regeneration in rodent models3,4,5,6,7,8,9,10. Unfortunately, few have had a positive impact in clinical practice. Direct intraoperative electrical stimulation of injured nerve tissue proximal to the site of repair has been demonstrated to enhance and accelerate functional recovery11,12, suggesting a novel nonpharmacological, bioelectric form of therapy that could complement existing surgical approaches. A significant limitation of this technique is that existing protocols are constrained to intraoperative use and limited therapeutic benefits13. Herein we introduce (i) a platform for wireless, programmable electrical peripheral nerve stimulation, built with a collection of circuit elements and substrates that are entirely bioresorbable and biocompatible, and (ii) the first reported demonstration of enhanced neuroregeneration and functional recovery in rodent models as a result of multiple episodes of electrical stimulation of injured nervous tissue.

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The data that support the findings of this study are available from the corresponding author on reasonable request.

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S.-K.K. is supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2018R1C1B5043901). H.M.L. is supported by a grant from NRF funded by the Korean government (MEST) (2011-0028612). Z.X. acknowledges support from the National Natural Science Foundation of China (grant no.11402134). Y.H. acknowledges support from National Science Foundation (grant nos. 1400169, 1534120, and 1635443). J.A.R. acknowledges support from DARPA and from the Center for Bio-Integrated Electronics at Northwestern University. We thank S. J. Robinson (Beckman Institute, University of Illinois at Urbana-Champaign) and K. Doty (Department of Comparative Biosciences Histology Service Laboratory, University of Illinois at Urbana-Champaign) for histology staining and images that greatly improved the manuscript.

Author information

J. Koo, S.-K.K., S.M.W., Y.-Y.C., S.C., and J.A.R. designed and made the device. J. Koo, M.R.M., S.-K.K., S.B.K., S.M.L., J. Kim, R.Z., J.S., D.V.H., A.B., H.M.L., W.Z.R., and J.A.R. conceived the idea and performed the experiments and analysis. M.R.M., M.S., P.G., N.B., J. Khalifeh, Z.S.Z., K.B., M.P., Y.Y., and W.Z.R. performed the animal surgery, collected the nerve regeneration data, and analyzed the immunohistochemistry. Z.X., K.L., B.J., and Y.H. designed the antennas and ran the electromagnetic simulation. J. Koo, S.-K.K., M.R.M., Y.H., W.Z.R., and J.A.R. wrote the manuscript.

Competing interests

The authors declare no competing interests.

Correspondence to Wilson Z. Ray or John A. Rogers.

Supplementary information

  1. Supplementary Text and Figures

    Supplementary Figures 1–17

  2. Reporting Summary

  3. Supplementary Video 1

    Twitch response by stimulating sciatic nerve with bioresorbable stimulator

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Fig. 1: Bioresorbable, wireless electrical stimulator as an electronic neuroregenerative medical device.
Fig. 2: Surgical implantation, operation, and acute demonstration of a bioresorbable, wireless electrical stimulator for the sciatic nerve in a rodent model.
Fig. 3: Accelerated regeneration of sciatic nerves injured by transection, treated with the use of biodegradable wireless stimulators.
Fig. 4: Effects of chronic electrical stimulation on functional nerve recovery.