Needle-Like Multifunctional Biphasic Microfiber for Minimally Invasive Implantable Bioelectronics.

Area of Science:

• Biomedical Engineering
• Materials Science
• Nanotechnology

Background:

• Implantable bioelectronics are crucial for precise disease diagnosis and treatment.
• Conventional rigid devices suffer from poor tissue integration and cause damage.
• Existing soft materials have limited practical applications.

Purpose of the Study:

• To develop a minimally invasive, soft implantable device with enhanced tissue integration.
• To create a multifunctional microfiber for biosensing and therapeutic applications.
• To overcome the limitations of current rigid and soft implantable electronics.

Main Methods:

• Fabrication of a needle-like stretchable microfiber with a liquid metal (LM) core and nanocomposite shell.
• Utilizing phase transition of LM for needle-like penetration and soft tissue conformance.
• Incorporating functional nanomaterials for low impedance and pH sensing.
• In vivo testing on stomach, muscle, and heart tissues.

Main Results:

• The microfiber can be stiffened by freezing for minimally invasive implantation.
• Upon thawing, the liquid metal core allows the device to regain soft, conforming properties.
• The device demonstrated low impedance, pH sensing, and electrical stimulation capabilities.
• The microfiber conformed effectively to various internal organs in vivo.

Conclusions:

• The developed biphasic microfiber offers a promising platform for soft, minimally invasive bioelectronics.
• It enables seamless tissue-device interfaces, improving diagnostic and therapeutic efficacy.
• Potential applications include electrophysiological recording, pH sensing, and electrical stimulation in vivo.