Implantable Electrodes With Anchored Hydrogels

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Implantable electrodes face issues with in vivo fouling due to protein adsorption, leading to increased impedance and reduced efficacy and battery lifetime, with existing biomaterial coatings being difficult to securely attach to noble metal electrodes.

Innovation Solution

Mechanically securing hydrogels to electrodes using anchoring features such as apertures, voids, or surface textures, and employing a non-swellable shell to constrain and stabilize the hydrogel, allowing for robust attachment without relying on covalent bonding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If covalent bonding is used to attach biomaterial to electrode, then attachment strength is improved, but ease of manufacture deteriorates for noble metal electrodes

Engineering Contradiction:

Improveattachment strengthVSAvoidease of manufacture

Core Design Contradiction:

StrengthVSEase of manufacture

Solution Approach 1:

The patent replaces chemical covalent bonding with mechanical anchoring features. The electrode surface is textured with micropillars, microgrooves, or other mechanical features that physically interlock with the hydrogel biomaterial, eliminating the need for chemical bonding steps that are difficult to achieve on noble metal surfaces.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent employs porous or textured electrode surfaces with controlled microporosity that allow hydrogel infiltration and mechanical interlocking. The porous structure provides increased surface area and physical anchoring points for the biomaterial without requiring chemical modification of the noble metal surface.

Inventive Principle:

Principle #31Porous materials

2Object-affected harmful factors

If hydrogel coating is applied to reduce protein adsorption, then biocompatibility is improved, but reliability deteriorates due to difficult secure attachment

Engineering Contradiction:

Improveprotein adsorption resistanceVSAvoidattachment reliability

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent replaces unreliable chemical bonding with reliable mechanical anchoring. The textured electrode surface provides physical interlocking features that securely hold the hydrogel coating in place, ensuring the biomaterial remains attached throughout implant operation without degradation from poor bonding.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent creates a composite structure combining the textured electrode substrate with the hydrogel coating layer. The mechanical features of the electrode and the viscoelastic properties of the hydrogel work together to create a robust, reliable attachment that maintains biocompatibility while ensuring long-term stability.

Inventive Principle:

Principle #40Composite materials

3Reliability

If fibrotic tissue deposition occurs, then impedance increases, but battery lifetime is reduced

Engineering Contradiction:

Improveimpedance stabilityVSAvoidbattery lifetime

Core Design Contradiction:

ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The patent applies preliminary anti-action by coating the electrode with hydrogel biomaterial that resists protein adsorption and fibrotic tissue formation before implantation occurs. This preventive coating reduces the rate of impedance increase over time, thereby extending battery lifetime without requiring higher initial power output.

Inventive Principle:

Principle #9Preliminary anti-action

Solution Approach 2:

The patent changes the surface properties of the electrode by applying a hydrogel coating that modifies the interface between the implant and biological tissue. This parameter change reduces protein adsorption and fibrotic encapsulation, maintaining lower impedance values and improving overall device performance and longevity.

Inventive Principle:

Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enhances the biocompatibility and longevity of implantable electrodes by reducing fibrotic responses and maintaining functionality for extended periods without the need for frequent replacements.

Implementation Method 1

The hydrogel can incorporate into the anchoring features to mechanically hold the hydrogel against the electrode

Methodology Applied

Scientific EffectHydrogel swelling: Hydrogel

Data Source

PatentUS10736572B2Implantable electrodes comprising mechanically anchored biocompatible hydrogels

Publication Date: 2020.08.11 VERILY LIFE SCIENCES LLC

AI summary

Biomaterials, such as hydrogels, can be mechanically secured to electrodes of an implantable device, such as electrodes made of noble metals. The hydrogel can be mechanically secured via anchoring features of the electrode. Anchoring features can include apertures, voids, textures, or other patterns created in or on the electrode. The hydrogel can incorporate into the anchoring features to mechanically hold the hydrogel against the electrode. The anchoring features, by being located in or on the electrode, can further increase the surface area of the electrode that is exposed to the hydrogel, which can facilitate the conduction of electrical signals between the electrode and surrounding biological tissue. The substrate supporting the electrode can include additional anchoring features that further assist in mechanically securing the hydrogel.