Chronic neural interfacing with cerebral cortex using single-walled carbon nanotube-polymer grids

Area of Science:

• Biomaterials science
• Neuroscience
• Medical device engineering

Background:

• Reliable brain electrical activity recording is crucial for brain-machine interface (BMI) technology.
• Developing advanced electrode arrays is essential for improving BMI performance and long-term use.

Purpose of the Study:

• To characterize novel single-walled carbon nanotube (SWCNT)-based electrode arrays grafted onto medium-density polyethylene (MD-PE) films.
• To evaluate the physico-chemical, physiological, histological, and immunohistochemical properties of these SWCNT arrays.

Main Methods:

• In vivo studies in rats involving two-month subdural electrocorticogram (ECoG) recordings.
• Ex vivo characterization of flexible SWCNT/polymer electrodes.
• Histological and immunohistochemical analyses to assess biocompatibility.

Main Results:

• SWCNT arrays successfully captured high-quality, stable ECoG signals over 8 weeks.
• Histological analyses indicated promising biocompatibility for chronic applications.
• The flexible and stretchable SWCNT arrays exhibited low electrode-tissue impedance and high compliance with cortical surfaces.

Conclusions:

• SWCNT arrays grafted onto MD-PE are suitable for flexible subdural ECoG recording devices.
• These arrays show potential as long-term neural implants for epilepsy monitoring and neuroprosthetic BMI applications.