Self-Folding Hybrid Substrate for Implantable Microelectrode Interfaces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current implantable microelectrodes face challenges in handling and accurate fabrication due to their three-dimensional curved shape, making them difficult to implant and interface with biological tissues effectively.
Innovation Solution
A substrate for implantable microelectrodes is developed, comprising a hybrid material with a hydrophobic and hydrophilic portion that self-folds around biological tissues upon exposure to a solvent, allowing for precise placement and stable interfacing through photopolymerization, enabling controlled deformation and improved signal transduction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If implantable microelectrodes are designed with a three-dimensional curved shape to interface with biological tissues, then the tissue contact and interface stability are improved, but the handling difficulty and fabrication accuracy deteriorate
Solution Approach 1:
The microelectrode structure is divided into a flat substrate portion and a curved electrode portion. The flat substrate enables easy handling and fabrication, while the curved electrode portion (formed by self-folding) provides effective tissue interface. This segmentation resolves the contradiction by separating the handling function from the interfacing function.
Solution Approach 2:
The substrate is prepared in a flat state before implantation, allowing precise fabrication and easy handling. The curved three-dimensional structure is formed in advance through self-folding mechanism upon contact with biological tissue or solvent, eliminating the need to handle complex curved structures during surgery.
2Ease of manufacture
If the substrate is made with uniform cross-linking density, then the manufacturing process is simplified, but the controlled deformation and self-folding capability deteriorate
Solution Approach 1:
The substrate is designed with non-uniform cross-linking density: a first region with lower cross-linking density that enables self-folding and deformation, and a second region with higher cross-linking density that maintains structural stability. This local differentiation allows the substrate to be manufactured with controlled properties that enable both ease of fabrication and adaptive self-folding.
Solution Approach 2:
The substrate employs a composite structure with regions of different cross-linking densities, creating material heterogeneity that provides both flexibility for folding and rigidity for stability. This composite approach resolves the contradiction between manufacturing simplicity and adaptive capability.
3Object-affected harmful factors
If the microelectrode structure is miniaturized to reduce implantation trauma, then the invasiveness is reduced, but the handling difficulty and fabrication precision requirements increase
Solution Approach 1:
The miniaturized microelectrode maintains a segmented design with flat substrate and curved electrode portions. The flat substrate can be manufactured with standard precision techniques, while the curved portion self-folds to achieve the complex three-dimensional shape, reducing the overall fabrication precision requirements despite miniaturization.
Solution Approach 2:
The microelectrode structure performs self-folding upon contact with tissue or solvent, automatically forming the required three-dimensional configuration without requiring precise pre-fabrication of curved shapes. This self-assembly mechanism reduces manufacturing precision requirements while maintaining the miniaturized form factor.
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
The self-folding capability of the substrate facilitates easier and more accurate implantation, enhances tissue contact, and improves signal transduction and stimulation efficiency.
Implementation Method 1
The substrate base layer (1) is obtained by curing a mixture (10) being photo-curable, comprising (a) a photoinitiator being able to be activated by exposure to light, (b) a first component (b) and (c) a second component (c)
Implementation Method 2
The first component (b) comprises a hydrophilic monomer or oligomer or polymer or copolymer which is able to form a hydrogel and to absorb water molecules
Implementation Method 3
The substrate base layer (1) is self-foldable according to the hydrophilicity/hydrophobicity differences between its first and second surfaces upon exposure to a solvent
Data Source
Figure 1(a)~3(b)
Figure 4(a)~5(b)
Figure 6
AI summary
A substrate (A) for implantable microelectrodes comprising a substrate base layer (1) being a polymer compound layer, wherein the substrate base layer (1) has a thickness (d1) in the z- direction and comprises a first surface (1-1) and a second surface (1-2), each of the first surface (1- 1) and the second surface (1-2) extending in the x-direction and the y-direction, the second surface (1-2) being opposite to the first surface (1-1) in the z-direction, wherein the substrate base layer (1) consists of a hybrid material of a hydrophobic part and a hydrophilic part, wherein the hybrid material is based on a mixture, the mixture comprising (a) a photoinitiator being able to be activated by exposure to light, (b) a first component comprising a first hydrophobic monomer, a first hydrophobic oligomer, a first hydrophobic polymer or a first hydrophobic copolymer, wherein the first hydrophobic monomer or oligomer or polymer or copolymer of the first component comprises a first functional group, wherein the first functional group is able to be activated by the activated photoinitiator, so that the first component is able to be polymerized through the first functional groups, (c) a second component comprising a hydrophilic monomer or a hydrophilic oligomer or a hydrophilic polymer or a hydrophilic copolymer, wherein the hydrophilic monomer or oligomer or polymer or copolymer comprises a second functional group, wherein the second functional group is able to be activated by the activated photoinitiator, so that the second component is able to be polymerized through the second functional groups, and so that the first component and the second component are able to be co-polymerized through the first functional groups and the second functional groups, and wherein the molecular weight (Mwa) of the first component is larger than the molecular weight (Mwb) of the second component, wherein the first surface (1-1) is more hydrophilic than the second surface (1-2).