Neural probe integrated with low-impedance electrodes implemented using vertically aligned carbon nanotubes for three-dimensional mapping of neural signals

Abstract

High-quality recordings of neural interfaces are crucial in advancing neuroscience research, but conventional electrodes with highly conductive materials have limitations due to their limited effective surface area. Here, we develop a neural probe integrated with an electrode implemented using vertically aligned carbon nanotubes (VACNTs) that remarkably improves recording capability. By directly synthesizing VACNT bundles on the electrode array of the neural probe, we successfully fabricate an electrode with the lowest area-specific impedance. Owing to the dramatically lowered impedance of the VACNT electrode, its signal-to-noise ratio increases by more than 3 times compared with that of a black Pt electrode with low impedance. Moreover, the number of spikes observed in the measured signals increases by more than 4 times. Notably, our VACNT electrode enables accurate mapping of the spatial distribution of neurons, demonstrating its potential to significantly advance neuroscience research through massive neural recordings with improved mapping capability. This powerful technology that maximizes electrode performance could pave the way for new discoveries and insights in the field of neuroscience.