Interfacing neurons both extracellularly and intracellularly using carbon-nanotube probes with long-term endurance.
This study demonstrates that carbon nanotubes (CNTs) can be fabricated into probes directly, with which neural activity can be monitored and elicited not only extracellularly but also intracellularly. Two types of CNT probes have been made and examined with the escape neural circuit of crayfish, Procambarus clarkia. The CNT probes are demonstrated to have comparable performance to conventional Ag/AgCl (silver/silver cloride) electrodes. Impedance measurement and cyclic voltammetry further indicate that the CNT probes transmit electrical signals through not only capacitive coupling but also resistive conduction. The resistive conduction facilitates the recording of postsynaptic potentials and equilibrium membrane potentials intracellularly as well as the delivery of direct-current stimulation. Furthermore, delivering current stimuli for a long term is found to enhance rather than to degrade the recording capability of the CNT probes. The mechanism of this fruitful result is carefully investigated and discussed. Therefore, our findings here support the suggestion that CNTs are suitable for making biocompatible, durable neural probes of various configurations for diverse applications.
Yeh
Shih-Rung
SR
Institute of Molecular Medicine, National Tsing Hua University (NTHU), 101, Sec. 2, Kuang-Fu Rd., Hsinchu, Taiwan 300.
Chen
Yung-Chan
YC
Su
Huan-Chieh
HC
Yew
Tri-Rung
TR
Kao
Hsiu-Hua
HH
Lee
Yu-Tao
YT
Liu
Tai-An
TA
Chen
Hsieh
H
Chang
Yen-Chung
YC
Chang
Pin
P
Chen
Hsin
H