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Parallel transmission in a synthetic nerve

Nature Chemistry volume 14, pages 650–657 (2022)Cite this article

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Abstract

Bioelectronic devices that are tetherless and soft are promising developments in medicine, robotics and chemical computing. Here, we describe bioinspired synthetic neurons, composed entirely of soft, flexible biomaterials, capable of rapid electrochemical signal transmission over centimetre distances. Like natural cells, our synthetic neurons release neurotransmitters from their terminals, which initiate downstream reactions. The components of the neurons are nanolitre aqueous droplets and hydrogel fibres, connected through lipid bilayers. Transmission is powered at these interfaces by light-driven proton pumps and mediated by ion-conducting protein pores. By bundling multiple neurons into a synthetic nerve, we have shown that distinct signals can propagate simultaneously along parallel axons, thereby transmitting spatiotemporal information. Synthetic nerves might play roles in next-generation implants, soft machines and computing devices.

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Fig. 1: Design of a bio-inspired synthetic nerve.
Fig. 2: Rapid sensory transduction and directional transmission in a synthetic neuron.
Fig. 3: Electrochemical communication in a synthetic neuron.
Fig. 4: Parallel transmission in a synthetic nerve.

Data availability

Data supporting the findings of this study are available within the paper and its Supplementary Information. Additional source data and design files that support these findings are available in the Figshare repository https://doi.org/10.6084/m9.figshare.17122127.v1. Alternatively, data are also available from the corresponding author upon reasonable request.

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Acknowledgements

Work in the H.B. group (including C.E.G.H. and V.R.S.) is supported by a European Research Council Advanced Grant (SYNTISU). C.E.G.H. was also supported by Oxford’s Doctoral Training Centre for Synthetic Biology, which is funded by the Engineering and Physical Sciences Research Council and the Biotechnology and Biological Sciences Research Council (EP/L016494/1). Microbial rhodopsins were prepared by J.V. and a gift from the A. Watts Group (Department of Biochemistry, University of Oxford, funded by DSTL UK (DSTLX-1000099768)) and αHL the gift of I. Cazimoglu (Bayley Group, University of Oxford). We thank D. Lunn for discussions regarding the use of elastomer. We also thank A. Walter and Y. Tanaka (Tecella) for their assistance.

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Author notes

  1. These authors contributed equally: Charlotte E. G. Hoskin, Vanessa Restrepo Schild.

Authors and Affiliations

  1. Chemistry Department, Oxford University, Oxford, UK

    Charlotte E. G. Hoskin, Vanessa Restrepo Schild & Hagan Bayley

  2. Doctoral Training Centre, Oxford University, Oxford, UK

    Charlotte E. G. Hoskin

  3. Biochemistry Department, Oxford University, Oxford, UK

    Javier Vinals

Authors
  1. Charlotte E. G. Hoskin
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  2. Vanessa Restrepo Schild
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  3. Javier Vinals
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  4. Hagan Bayley
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Contributions

C.E.G.H., V.R.S., and H.B. conceived the ideas behind the project, discussed the data and wrote the manuscript. C.E.G.H. (with assistance from V.R.S.) carried out the experiments and analysed the data. J.V. prepared the microbial rhodopsins.

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Correspondence to Hagan Bayley.

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Supplementary Figs. 1–31, Materials and Methods, theoretical considerations and references.

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Hoskin, C.E.G., Schild, V.R., Vinals, J. et al. Parallel transmission in a synthetic nerve. Nat. Chem. 14, 650–657 (2022). https://doi.org/10.1038/s41557-022-00916-1

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