Improved in vitro electrophysiology using 3D-structured microelectrode arrays with a micro-mushrooms islets architecture capable of promoting topotaxis

Abstract

A novel MEA architecture with excellent electrophysiological recordings is presented, where planar microelectrodes are replaced by localized 3 × 3 arrays of mushroom-shaped microstructures. The micro-mushrooms in this islets configuration are not for membrane engulfment but rather for somata entrapment and neurites embracement. As extracellular signals have a significant contribution from axons initial segment, this MEA design also addresses the electrode-neurites electrical coupling. These islets act as strong physical cues, causing topotaxis and increasing by two-fold the probability for somata to localize in the islets. We carry this topotaxis study not only with rat cortical neurons but also with human-derived SH-SY5Y cells.