Hydrogel Adhesive Integrated-Microstructured Electrodes for Cuff-Free, Less-Invasive, and Stable Interface for Vagus...

Area of Science:

• Biomedical Engineering
• Neuroscience
• Materials Science

Background:

• Vagus nerve stimulation (VNS) is a key treatment for neurological disorders.
• Current VNS implantation involves surgical risks like nerve or vascular damage due to nerve isolation and cuffing.

Purpose of the Study:

• To develop a novel, less invasive, cuff-free microdevice for vagus nerve interfacing.
• To minimize surgical risks associated with VNS implantation.

Main Methods:

• A stretchable microdevice with a novel hydrogel adhesive was designed.
• Kirigami structures were incorporated to ensure uniform tissue contact and accommodate hydrogel hydration changes.
• Device adhesion and functionality were tested on a rodent vagus nerve model in physiological fluid.

Main Results:

• The device demonstrated robust adhesion to the vagus nerve without isolation or cuffing.
• Stable and clear evoked compound action potentials (~1500 µV) were recorded from C-fibers at 0.4 mA.
• The hydrogel adhesive successfully crosslinked on biological tissue.

Conclusions:

• The developed hydrogel adhesive-integrated microdevice offers a safer, cuff-free alternative for vagus nerve interfacing.
• This innovative platform reduces risks during VNS implantation by avoiding nerve isolation.
• The technology shows promise for interfacing with delicate neural and vascular structures.