Neuromuscular interfaces are required to translate bioelectronic technologies for application in clinical medicine. Here, by leveraging the robotically controlled ink-jet deposition of low-viscosity conductive inks, extrusion of insulating silicone pastes and in situ activation of electrode surfaces via cold-air plasma, we show that soft biocompatible materials can be rapidly printed for the on-demand prototyping of customized electrode arrays well adjusted to specific anatomical environments, functions and experimental models. We also show, with the monitoring and activation of neuronal pathways in the brain, spinal cord and neuromuscular system of cats, rats and zebrafish, that the printed bioelectronic interfaces allow for long-term integration and functional stability. This technology might enable personalized bioelectronics for neuroprosthetic applications.
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The main data supporting the results in this study are available within the paper and its Supplementary Information file. The raw and analysed datasets generated during the study are too large to be publicly shared, but they are available for research purposes from the corresponding authors on reasonable request.
The code used to program the printer paths can be found at https://sourceforge.net/projects/g-code-processor.
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We acknowledge funding from the following sources: the European Research Council (804005; IntegraBrain), Saint-Petersburg State University (project 51134206; funding to O.G. and N.M. for animal facility and biocompatibility studies, and validation of the implants on in vivo models), Technische Universität Dresden, the Russian Foundation for Basic Research (grants 20-015-00568-a (for the urodynamic study) and 18-33-20062-mol_a_ved (for developing the optimal electrode array configuration)), Deutsche Forschungsgemeinschaft (MI 2117/1-1) and the Volkswagen Foundation (Freigeist 91 690). We thank D. E. Korzhevskiy (immunohistochemistry), Y. I. Sysoev (zebrafish model), A. V. Goriainova (functional tests) and T. Kurth (electron microscopy) for help and expertise.
The authors declare no competing interests.
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Supplementary Figs. 1–18, captions for Supplementary Videos 1–3 and references.
Hybrid printing technology for personalized soft neuromuscular interfaces (NeuroPrint).
Facilitation of the spinal locomotor network by the NeuroPrint array.
Long-term biointegration of the NeuroPrint technology.
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Afanasenkau, D., Kalinina, D., Lyakhovetskii, V. et al. Rapid prototyping of soft bioelectronic implants for use as neuromuscular interfaces. Nat Biomed Eng 4, 1010–1022 (2020). https://doi.org/10.1038/s41551-020-00615-7
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