A Glial‐Silicon Nanowire Electrode Junction Enabling Differentiation and Noninvasive Recording of Slow Oscillations from Primary Astrocytes
Emanuela Saracino, Luca Maiolo, Davide Polese, Marianna Semprini, Ana I. Borrachero‐Conejo, Jacopo Gasparetto, Stefano Murtagh, Margherita Sola, Lorenzo Tomasi, Francesco Valle, Luca Pazzini, Francesco Formaggio, Michela Chiappalone, Saber M. Hussain, Marco Caprini, Michele Muccini, Luigi Ambrosio, G. Fortunato, R. Zamboni, Annalisa Convertino, Valentina Benfenati
Abstract
The correct human brain function is dependent on the activity of non-neuronal cells called astrocytes. The bioelectrical properties of astrocytes in vitro do not closely resemble those displayed in vivo and the former are incapable of generating action potential; thus, reliable approaches in vitro for noninvasive electrophysiological recording of astrocytes remain challenging for biomedical engineering. Here it is found that primary astrocytes grown on a device formed by a forest of randomly oriented gold coated-silicon nanowires, resembling the complex structural and functional phenotype expressed by astrocytes in vivo. The device enables noninvasive extracellular recording of the slow-frequency oscillations generated by differentiated astrocytes, while flat electrodes failed on recording signals from undifferentiated cells. Pathophysiological concentrations of extracellular potassium, occurring during epilepsy and spreading depression, modulate the power of slow oscillations generated by astrocytes. A reliable approach to study the role of astrocytes function in brain physiology and pathologies is presented.