Flexible 3D Kirigami Probes for In Vitro and In Vivo Neural Applications

This study presents a scalable kirigami-based fabrication method for flexible 3D microelectrode arrays (MEAs) designed for in vitro and in vivo neural interfacing. The 3D kirigami MEAs, fabricated from parylene-C using matched-die thermoforming, integrate both surface and penetrating electrodes to enable volumetric electrophysiological recordings. Mechanical and electrochemical characterization validated high yield, low impedance, and mechanical stability under insertion and thermal cycling. Using human cortical slices and live mouse models, the probes successfully captured seizure-like activity and depth-resolved neural responses across cortical layers. The study demonstrates that flexible kirigami MEAs can achieve scalable, high-density, minimally invasive 3D neural interfacing for neurophysiological and brain–machine interface applications.