Multi-Functional HD-MEA Platform for High-Resolution Impedance Imaging and Electrophysiological Recordings of Brain Slices

We present a high-resolution impedance imaging and electrophysiological recording platform and demonstrate its capabilities with brain slices. The platform is easy to operate featuring an efficient data acquisition system and user-friendly software that runs on a host computer. The data acquisition platform relies on an FPGA system that enables bidirectional communication between the host computer and the high-density microelectrode array (HD-MEA). The software on the host computer helps to record and online visualize the HD-MEA data. Moreover, online filtering (and spike detection) features rapid visual feedback that enables the experimenter to reconfigure the HD-MEA. The platform includes a custom-designed pressing device to affix the brain slice on the HD-MEA and maintain good electrode-tissue contact. We validated the system with mouse acute cerebellar brain slices; high-resolution impedance imaging and electrophysiological recordings yielded data that were consistent with optical imaging. Moreover, the platform enabled the selection of highly active regions for recordings with high-density configurations and monitor multiple neurons in the same area at single-cell resolution.