Interfacing Neurons with Nanostructured Electrodes Modulates Synaptic Circuit Features

Abstract

Understanding neural physiopathology requires advances in nanotechnology‐based interfaces, engineered to monitor the functional state of mammalian nervous cells. Such interfaces typically contain nanometer‐size features for stimulation and recording as in cell‐non‐invasive extracellular microelectrode arrays. In such devices, it turns crucial to understand specific interactions of neural cells with physicochemical features of electrodes, which could be designed to optimize performance. Herein, versatile flexible nanostructured electrodes covered by arrays of metallic nanowires are fabricated and used to investigate the role of chemical composition and nanotopography on rat brain cells in vitro. By using Au and Ni as exemplary materials, nanostructure and chemical composition are demonstrated to play major roles in the interaction of neural cells with electrodes. Nanostructured devices are interfaced to rat embryonic cortical cells and postnatal hippocampal neurons forming synaptic circuits. It is shown that Au‐based electrodes behave similarly to controls. Contrarily, Ni‐based nanostructured electrodes increase cell survival, boost neuronal differentiation, and reduce glial cells with respect to flat counterparts. Nonetheless, Au‐based electrodes perform superiorly compared to Ni‐based ones. Under electrical stimulation, Au‐based nanostructured substrates evoke intracellular calcium dynamics compatible with neural networks activation. These studies highlight the opportunity for these electrodes to excite a silent neural network by direct neuronal membranes depolarization.

Adhesion of Neurons and Glial Cells with Nanocolumnar TiN Films for Brain-Machine Interfaces

“…They showed that nanostructured platinum coatings of neuroelectrodes, as well as unstructured surfaces, do not exhibit cytotoxic effects on the SH-SY5Y cells. Dominguez-Bajo et al [62] grew neuronal cells derived from rats on both flat and nanostructured nickel and gold electrodes. Increased neural cell survival, improved neuronal differentiation, and fewer glial cells were measurable on nanostructured nickel in comparison to its flat counterpart.…”

PEDOT:PSS‐Based Bioelectronic Devices for Recording and Modulation of Electrophysiological and Biochemical Cell Signals

“…Unlike the sharp and patch-clamp electrodes, the noninvasive extracellular techniques enable the simultaneous recording and stimulation of electrogenic cells over long time periods without mechanically damaging the cell membrane. [12,13,14] c) Macroscale measurement of wide areas brain's activities: [15] This method can be used to examine the functional connectivity of different regions in the brain, but with a lower spatial resolution. Accordingly, micro-and mesoscale extracellular recording sensors possess the greatest potential to facilitate simultaneous, multisite, long-term, and multiscale in vitro and in vivo recording from large populations of neurons.…”

Polystyrene Nanopillars with Inbuilt Carbon Nanotubes Enable Synaptic Modulation and Stimulation in Interfaced Neuronal Networks

“…The latter was obtained drilling an 8 mm‐diameter hole in the bottom of a 35 mm PS petri dish (Falcon). [ 42 ] To ensure neuronal viability and avoid medium leak during culture the sample assembly was mounted on the petri dish hole using PDMS silicone elastomer (Sylgard 184, Dow Corning Co.). [ 37 ] This assembly offered easy access for the stimulating electrode to contact in a dry environment the PS‐CNT NPs from the bottom side (see the sketch in Figure 5A).…”