Optimizing Electrode Design for Functional Activation of Human Pluripotent Stem Cell‐Derived Cardiomyocytes

Electrical pacing is a key strategy for enhancing the functional maturity of human pluripotent stem cell‐derived cardiomyocytes (hPSC‐CMs) by preserving the contractile phenotype of explanted cardiomyocytes or promoting the development of adult‐like features in immature ones. Electrical stimulation platforms typically employ opaque electrodes positioned at the periphery of the culture dish, limiting the area that can be stimulated and necessitating high currents to activate all the cells. Here, we systematically evaluated how electrode material and spatial configuration influence the response of hPSC‐CMs. We compared transparent indium–tin‐oxide and gold electrodes arranged in three different configurations to vary electrode–cell distance, active surface area, and field orientation. Using electrochemical impedance spectroscopy and finite element modeling, we characterized the electrical properties of each setup. We assessed the two‐dimensional (2D) hPSC‐CM monolayer contractility under identical stimulation protocols across all configurations. Among all tested setups, the vertical configuration was the most efficient in eliciting robust contractile responses of mature hPSC‐CMs, and gold electrodes showed higher efficiency. However, electrical pacing did not enhance maturation markers in hPSC‐CMs when applied as a training method. These findings provide design principles for optimizing electrical stimulation systems in cardiac tissue engineering, with implications for disease modeling and cell‐based regenerative therapies.