16-Channel Organic Electrochemical Transistor Array for In Vitro Conduction Mapping of Cardiac Action Potential

16-Channel organic electrochemical transistor arrays (OECTs) are developed for mapping the propagation and studying the characteristics of action potentials of primary cardiomyocytes. The physiological activities of a rat cardiomyocyte monolayer during a long-term culturing is revealed by this biocompatible, low-cost, and high transconductance organic electronic device. OECT has great potential to be used in cardiac and neuronal drug screening.