Implantable Biosupercapacitor Inspired by the Cellular Redox System

Area of Science:

• Biomedical Engineering
• Materials Science
• Electrochemistry

Background:

• Implantable energy storage is crucial for biomedical devices.
• Traditional pseudocapacitive materials face biocompatibility challenges in vivo.
• Cellular redox systems offer a biocompatible model for energy transduction.

Purpose of the Study:

• To develop an implantable carbon nanotube (CNT) yarn supercapacitor.
• To utilize a cellular redox biomolecule-inspired system for energy storage.
• To evaluate the supercapacitor's performance in physiological conditions and in vivo.

Main Methods:

• Fabrication of CNT yarn electrodes with electrochemically deposited nicotinamide adenine dinucleotide (NAD) and benzoquinone.
• Testing of electrode capacitance and stability under physiological conditions (PBS, serum).
• Assessment of electrochemical stability through charge/discharge cycles and mechanical deformation tests.
• In vivo implantation and performance evaluation in a rat model.

Main Results:

• NAD/benzoquinone/CNT yarn electrodes achieved a maximum area capacitance of 55.73 mF/cm² under physiological conditions.
• The electrodes demonstrated excellent stability with negligible capacitance loss after 10,000 cycles and deformation.
• Stable in vivo electrical performance was observed after implantation in a rat's abdominal cavity.

Conclusions:

• The developed CNT yarn supercapacitor, inspired by cellular redox systems, is biocompatible and suitable for in vivo applications.
• This redox biomolecule-applied platform offers a novel approach for implantable energy storage devices.
• The study highlights the potential of NAD/benzoquinone/CNT yarn for safe and effective medical energy solutions.