Soft 3D bioelectronic mesh maps 91% of mini brain neural networks

Researchers at Northwestern University and Shirley Ryan AbilityLab have developed a soft, three-dimensional bioelectronic mesh that can envelop lab-grown human neural organoids—mini brains derived from stem cells—and record electrical activity across 91% of their surface. This device overcomes a significant limitation of traditional flat, rigid electrodes that only sample limited areas, thereby enabling comprehensive monitoring of neural network activity. The mesh contains up to 240 microelectrodes, each about the size of a single cell, arranged in a porous, flexible lattice that conforms to the organoid’s curved shape without impeding nutrient flow or tissue viability. The 3D mesh is created through a controlled mechanical buckling process, allowing it to transform from a flat sheet into a shape-matched scaffold that gently wraps the spherical organoid. This design facilitates detailed three-dimensional mapping of synchronized neural oscillations and large-scale communication across the entire network, which was previously difficult to observe. Beyond recording, the system can also stimulate the tissue electrically, as