Spatiotemporal characteristics of neural activity in tibial nerves with carbon nanotube yarn electrodes

X Yu; J Y Su; J Y Guo; X H Zhang; R H Li; X Y Chai; Y Chen; D G Zhang; J G Wang; X H Sui; D M Durand

doi:10.1016/j.jneumeth.2019.108450

Spatiotemporal characteristics of neural activity in tibial nerves with carbon nanotube yarn electrodes

J Neurosci Methods. 2019 Dec 1:328:108450. doi: 10.1016/j.jneumeth.2019.108450. Epub 2019 Sep 29.

Authors

X Yu¹, J Y Su¹, J Y Guo¹, X H Zhang², R H Li¹, X Y Chai¹, Y Chen¹, D G Zhang³, J G Wang⁴, X H Sui⁵, D M Durand⁶

Affiliations

¹ School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
² Innovation Center for Textile Science and Technology, Donghua University, Shanghai, China.
³ School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China.
⁴ Shanghai Institute of Hypertension, Department of Hypertension, Shanghai Jiao Tong University School of Medicine Affiliated Ruijin Hospital, Shanghai, China.
⁵ School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China. Electronic address: suixhong@sjtu.edu.cn.
⁶ Neural Engineering Center, Department of Biomedical Engineering, Case Western Reserve University, Cleveland, USA. Electronic address: dxd6@case.edu.

PMID: 31577919
DOI: 10.1016/j.jneumeth.2019.108450

Abstract

Background: Reliable interfacing with peripheral nervous system is essential to extract neural signals. Current implantable peripheral nerve electrodes cannot provide long-term reliable interfaces due to their mechanical mismatch with host nerves. Carbon nanotube (CNT) yarns possess excellent mechanical flexibility and electrical conductivity. It is of great necessity to investigate the selectivity of implantable CNT yarn electrodes.

New method: Neural interfaces were fabricated with CNT yarn electrodes insulated with Parylene-C. Acute recordings were carried out on tibial nerves of rats, and compound nerve action potentials (CNAPs) were electrically evoked by biphasic current stimulation of four toes. Spatiotemporal characteristics of neural activity and spatial selectivity of the electrodes, denoted by selectivity index (SI), were analyzed in detail.

Results: Conduction velocities of sensory afferent fibers recorded by CNT yarn electrodes varied between 4.25 m/s and 37.56 m/s. The SI maxima for specific toes were between 0.55 and 0.99 across seven electrodes. SIs for different CNT yarn electrodes are significantly different among varied toes.

Comparison with existing methods: Most single CNT yarn electrode with a ∼ 500 μm exposed length can be sensitive to one or two specific toes in rodent animals. While, it is only possible to discriminate two non-adjacent toes by multisite TIME electrodes.

Conclusion: Single CNT yarn electrode exposed ∼ 500 μm showed SI values for different toes comparable to a multisite TIME electrode, and had high spatial selectivity for one or two specific toes. The electrodes with cross section exposed could intend to be more sensitive to one specific toe.

Keywords: Carbon nanotube yarn electrodes; Neuroprostheses; Peripheral nervous system; Spatial selectivity; Temporal characteristics.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Electrodes, Implanted*
Electrophysiological Phenomena / physiology*
Male
Muscle, Skeletal / physiology*
Nanotubes, Carbon*
Neural Prostheses*
Neurons, Afferent / physiology*
Neurosciences / instrumentation*
Peripheral Nervous System / physiology*
Rats
Rats, Sprague-Dawley

Substances

Nanotubes, Carbon