Flexible polyimide-based intracortical electrode arrays with bioactive capability

TLDR

Advanced neuroprosthetic systems require safe, efficacious multichannel neural interfaces to improve quality of life for deaf, blind, or paralyzed individuals. This study presents a thin‑film, polyimide‑based, multichannel intracortical Bio‑MEMS interface fabricated using standard planar photolithographic CMOS‑compatible techniques. The device uses a flexible polyimide substrate that can be shaped into 3‑D designs, supports selective bioactive species attachment for favorable tissue response, and incorporates an integrated polyimide cable for high‑density connector contact. In vivo and in vitro testing indicates these arrays are promising candidates for long‑term neural implants.

Abstract

The promise of advanced neuroprosthetic systems to significantly improve the quality of life for a segment of the deaf, blind, or paralyzed population hinges on the development of an efficacious, and safe, multichannel neural interface for the central nervous system. The candidate implantable device that is to provide such an interface must exceed a host of exacting design parameters. We present a thin-film, polyimide-based, multichannel intracortical Bio-MEMS interface manufactured with standard planar photo-lithographic CMOS-compatible techniques on 4-in silicon wafers. The use of polyimide provides a mechanically flexible substrate which can be manipulated into unique three-dimensional designs. Polyimide also provides an ideal surface for the selective attachment of various important bioactive species onto the device in order to encourage favorable long-term reactions at the tissue-electrode interface. Structures have an integrated polyimide cable providing efficient contact points for a high-density connector. This report details in vivo and in vitro device characterization of the biological, electrical and mechanical properties of these arrays. Results suggest that these arrays could be a candidate device for long-term neural implants.