1 research outputs found
Electrical Neural Stimulation and Simultaneous <i>in Vivo</i> Monitoring with Transparent Graphene Electrode Arrays Implanted in GCaMP6f Mice
Electrical stimulation using implantable
electrodes is widely used to treat various neuronal disorders such
as Parkinson’s disease and epilepsy and is a widely used research
tool in neuroscience studies. However, to date, devices that help
better understand the mechanisms of electrical stimulation in neural
tissues have been limited to opaque neural electrodes. Imaging spatiotemporal
neural responses to electrical stimulation with minimal artifact could
allow for various studies that are impossible with existing opaque
electrodes. Here, we demonstrate electrical brain stimulation and
simultaneous optical monitoring of the underlying neural tissues using
carbon-based, fully transparent graphene electrodes implanted in GCaMP6f
mice. Fluorescence imaging of neural activity for varying electrical
stimulation parameters was conducted with minimal image artifact through
transparent graphene electrodes. In addition, full-field imaging of
electrical stimulation verified more efficient neural activation with
cathode leading stimulation compared to anode leading stimulation.
We have characterized the charge density limitation of capacitive
four-layer graphene electrodes as 116.07–174.10 μC/cm<sup>2</sup> based on electrochemical impedance spectroscopy, cyclic voltammetry,
failure bench testing, and <i>in vivo</i> testing. This
study demonstrates the transparent ability of graphene neural electrodes
and provides a method to further increase understanding and potentially
improve therapeutic electrical stimulation in the central and peripheral
nervous systems