Flexible Micropillar Electrode Arrays for In Vivo Neural Activity Recordings

Flexible electronics that can form tight interfaces with neural tissues hold great promise for improving the diagnosis and treatment of neurological disorders and advancing brain/machine interfaces. Here, the facile fabrication of a novel flexible micropillar electrode array (μPEA) is described based on a biotemplate method. The flexible and compliant μPEA can readily integrate with the soft surface of a rat cerebral cortex. Moreover, the recording sites of the μPEA consist of protruding micropillars with a nanoscale surface roughness that ensures tight interfacing and efficient electrical coupling with the nervous system. As a result, the flexible μPEA allows for in vivo multichannel recordings of epileptiform activity with a high signalto-noise ratio. The ease of preparation and high flexibility make the μPEA an attractive tool for in vivo spatiotemporal mapping of neural activity.