Hydrogel Coatings for Improving the Efficiency of Implanted Electrode Arrays

Introduction

Implanted electrode arrays are a key component of neuroprosthetic systems designed to restore functions lost through injury or degeneration of the nervous system.

Current Materials

Electrode arrays currently used in clinical practice are made from metals (e.g., Platinum, PtIr alloys) encapsulated in silicone. These materials strike a compromise between electrical properties on one side and good tissue integration on the other.

Challenges with Current Electrode Arrays

For example, the limited charge injection capacity and high mechanical stiffness of metal electrodes are implicated in challenges with:

• Long-term stability
• Mechanical failure
• Formation of a glial scar
• Electrode miniaturization

COATARRAY Project Overview

In the COATARRAY project, we will develop a specialized coating designed to radically improve the electrical and mechanical performance of electrode arrays. The coating is based on a bioinspired hydrogel material further endowed with electrical conductivity via incorporation of conductive polymers.

Coating Application

The coating can be assembled on a variety of ready-made electrode arrays designed for different applications.

Testing and Analysis

In this project, we will conduct a thorough electrical characterization of the coating as well as:

1. Mechanical tests
2. Insertion tests
3. Sterilization tests
4. Cytocompatibility tests
5. Accelerated aging tests

In combination with analysis of the regulatory and commercial landscape, this project will establish an essential milestone towards clinical translation of the COATARRAY technology.

Potential Impact

If successful, our approach to improving the performance of implanted electrode arrays can lead to better clinical outcomes for established neuroprosthetic systems (cochlear implants, deep brain, and spinal cord stimulation) but also to the development of promising new treatments.