Fabrication and in vivo 2-photon microscopy validation of transparent PEDOT:PSS microelectrode arrays

Gerwin Dijk; Attila Kaszas; Jolien Pas; Rodney Philip O'Connor

doi:10.1038/s41378-022-00434-7

Fabrication and in vivo 2-photon microscopy validation of transparent PEDOT:PSS microelectrode arrays

Microsyst Nanoeng. 2022 Aug 29:8:90. doi: 10.1038/s41378-022-00434-7. eCollection 2022.

Authors

Gerwin Dijk^{1

2}, Attila Kaszas¹, Jolien Pas², Rodney Philip O'Connor¹

Affiliations

¹ Mines Saint-Etienne, Centre CMP, Department of Bioelectronics, Gardanne, 13541 France.
² Panaxium SAS, Aix-en-Provence, 13100 France.

Abstract

Transparent microelectrode arrays enable simultaneous electrical recording and optical imaging of neuronal networks in the brain. Electrodes made of the conducting polymer poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS) are transparent; however, device fabrication necessitates specific processes to avoid deterioration of the organic material. Here, we present an innovative fabrication scheme for a neural probe that consists of transparent PEDOT:PSS electrodes and demonstrate its compatibility with 2-photon microscopy. The electrodes show suitable impedance to record local field potentials from the cortex of mice and sufficient transparency to visualize GCaMP6f-expressing neurons underneath the PEDOT:PSS features. The results validate the performance of the neural probe, which paves the way to study the complex dynamics of in vivo neuronal activity with both a high spatial and temporal resolution to better understand the brain.

Keywords: Engineering; Materials science.