Liquid metal neuro-electrical interface

Abstract

Liquid metal (LM), an emerging functional material, plays increasing roles in biomedical and healthcare areas. It has particular values in neural interfaces as it combines high conductivity, flowability, and biocompatibility properties. Neuro-electrical interfaces (NEIs) are effective tools to provide a bridge between the nervous system and the outside world. The main target of developing neural interfaces is to help disabled people repair damaged nerves and enhance human capacity above normal ability. This article systematically summarizes LM-based neural interface technologies, including neural electrodes for electrical signal acquisition and administration of electrical stimulation and nerve guidance conduits for neural connectivity and functional reconstruction. The discussion begins with an overview of the fundamental properties associated with LM materials involved in the field of neural interface applications. The fabrication methods of LM-based neuro-electrodes and conduits are then introduced, and the current development status of LM-based neuro-electrodes and conduits is elaborated. Finally, the prospects and possible challenges of LM-based neural interfaces are outlined.

Keywords

Liquid metal / neural interface / neural electrode / neural guidance conduit

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