posted on 2020-06-24, 20:30authored byNuan Chen, Baiwen Luo, Anoop C. Patil, Jiahui Wang, Gil Gerald Lasam Gammad, Zhigao Yi, Xiaogang Liu, Shih-Cheng Yen, Seeram Ramakrishna, Nitish V. Thakor
Neural
electrodes are developed for direct communication with neural
tissues for theranostics. Although various strategies have been employed
to improve performance, creating an intimate electrode–tissue
interface with high electrical fidelity remains a great challenge.
Here, we report the rational design of a tunnel-like electrode coating
comprising poly(3,4-ethylenedioxythiophene) (PEDOT) and carbon nanotubes
(CNTs) for highly sensitive neural recording. The coated electrode
shows a 50-fold reduction in electrochemical impedance at the biologically
relevant frequency of 1 kHz, compared to the bare gold electrode.
The incorporation of CNT significantly reinforces the nanotunnel structure
and improves coating adhesion by ∼1.5 fold. In vitro primary neuron culture confirms an intimate contact between neurons
and the PEDOT-CNT nanotunnel. During acute in vivo nerve recording, the coated electrode enables the capture of high-fidelity
neural signals with low susceptibility to electrical noise and reveals
the potential for precisely decoding sensory information through mechanical
and thermal stimulation. These findings indicate that the PEDOT-CNT
nanotunnel composite serves as an active interfacing material for
neural electrodes, contributing to neural prosthesis and brain–machine
interface.