Adsorbed Eutectic GaIn Structures on a Neoprene Foam for Stretchable MRI Coils

Area of Science:

• Materials Science
• Electrical Engineering
• Biomedical Engineering

Background:

• Stretchable electronic conductors are crucial for wearable devices and advanced medical imaging.
• Eutectic gallium-indium (eGaIn) alloy offers excellent conductivity and stretchability.
• Polychloroprene (neoprene) foam provides a flexible and conformable substrate.

Purpose of the Study:

• To develop and characterize stretchable conductors based on eGaIn on a neoprene substrate.
• To investigate the relationship between eGaIn loading and strain-sensitivity of electrical resistance.
• To demonstrate the application of these conductors as stretchable coils for magnetic resonance imaging (MRI).

Main Methods:

• Stencil printing of eGaIn alloy onto a neoprene foam substrate.
• Controlled variation of eGaIn amount to tune conductor properties.
• Electrical resistance measurements under varying strain levels.
• Fabrication of stretchable on-body coils for MRI signal reception.

Main Results:

• Conductors exhibited tunable strain-sensitivity of electrical resistance, ranging from 5% to 300% at 100% strain.
• Increased eGaIn loading led to higher strain-sensitivity due to cell filling.
• Successful acquisition of MRI images using the developed stretchable coil on an orange.
• Comparison of image quality with a conventional rigid copper coil.

Conclusions:

• The developed eGaIn-on-neoprene conductors offer tunable stretchability and strain-sensitivity.
• These materials are suitable for creating stretchable on-body coils for clinical MRI applications.
• The study demonstrates a promising approach for advanced, conformable medical imaging devices.