Ultra-Flexible Neural Probes with Electrochemical Modified Electrodes for Reliable, Chronical Recording

We report a class of flexible nanofabricated neural probes with electrochemical modified electrodes that are able to achieve a reliable recording of neural activities down to a single neuron level with high signal noise ratio ($\text{SNR} > 7$) for over 8 weeks with a minimally invasive in-vivo implantation surgery. The yield of detected single unit activity is over 45%, which is considerably higher than many conventional neural probes (∼25%). PEDOT electrochemical modification of ultra-flexible electrode surface from 32 channels (which are mainly limited by our data acquisition/processing capabilities and can be readily scaled up) effectively lowers the probe impedance and improves the signal quality. Our nanofabricated neural probes offer new opportunities as high performance neural interfaces for long-term, stable and accurate neuronal network signals tracking and recording.