Electrical Interconnects Fabricated From Biodegradable Conductive Polymer Composites

Area of Science:

• Materials Science
• Biomedical Engineering
• Polymer Science

Background:

• Transient implantable medical devices require functional electronic components that degrade over time.
• Biodegradable materials offer a solution to minimize long-term foreign body response.
• Developing reliable biodegradable electrical interconnects is crucial for advanced medical devices.

Purpose of the Study:

• To develop and characterize biodegradable electrical interconnects for transient implantable medical devices.
• To investigate the electrical properties of conductive polymer composites under physiological degradation.
• To assess the feasibility of these interconnects for integration into implantable systems.

Main Methods:

• Fabrication of conductive polymer composites using iron (Fe) microparticles and polycaprolactone (PCL).
• Micropatterning of Fe-PCL composites into daisy chain structures.
• Evaluation of electrical resistivity and resistance under simulated physiological degradation conditions.
• System integration with a commercial humidity sensor.

Main Results:

• Electrical percolation achieved at 17% iron volume fraction.
• Higher iron fractions (e.g., 40%vf) showed more stable electrical resistivity during degradation.
• A tenfold increase in resistivity for 40%vf Fe-PCL composites in a packaged, degraded environment.
• Successful micropatterning and demonstration of electrical interconnect functionality.
• Achieved an electrical lifetime exceeding 5 days for packaged daisy chain structures.

Conclusions:

• Micropatterned Fe-PCL composites are process-compatible for interconnect applications in transient implantable devices.
• The developed biodegradable interconnects exhibit promising electrical stability and longevity for medical applications.
• Fe-PCL composites represent a viable material solution for transient electronic systems in vivo.