Perforated silicon dices with integrated nerve guidance channels for interfacing peripheral nerves

It has been shown previously that peripheral nerve axons are regenerating through microvias in silicon devices. A major challenge is the design of a biocompatible integrated neural connector allowing simultaneous, multi-site recordings or stimulation of axons in nerve bundles and to establish a reliable mechanical and electrical connection. This paper describes on-going research in the framework of an European project aimed to develop an implantable neural microsystem comprising various designs of perforated dices, multiple electrodes with on-chip integrated preprocessing circuitry, functional guidance channels for support and fixation of regenerating axons, and interconnection assemblies for bidirectional nervous signal transmission. Special emphasis is given on a light-weight design of the device and on the biocompatible integration and packaging of the chip. In this paper, we report about the microfabrication of the perforated dices, their incorporation into biocompatible guidance channels, and about in vitro and in vivo biocompatibility testing of materials applied.