Non-Invasive electrophysiological monitoring of cardiac organoids using 3D-Net-assisted microelectrodes array platform.

The rapid advancement of organoids has increased interest in replacing conventional 2D alternatives to animal testing. In drug development, cardiotoxicity assessment is essential, and electrophysiological signals from cardiomyocytes serve as key biomarkers. Accordingly, planar 2D microelectrode array (MEA) chips are widely used. However, cardiomyocytes-based platform fails to reproduce complex in vivo physiological responses, leading to the combination of human cardiac organoids (hCdOs) with 3D sensors. Most of these approaches remain in the research stage and lack standardization. Therefore, there is still a need for methods that can stably evaluate organoids using commercially available 2D MEA chips. In this study, a silicon-based 3D-Net was introduced to enable stable monitoring of hCdOs electrophysiological signals on MEA chip. hCdOs fabricated using established protocols showed morphological and functional reproducibility suitable for drug testing. The 3D-Net prevented organoid flotation, ensured sufficient medium supply, and enabled measurements beyond acute assessment periods without functional impairment. Drug responsiveness varied significantly depending on the presence of 3D-Net and the volume of drug-containing medium. The 3D-Net platform overcomes the limitations of MEA, providing an effective and non-invasive method for functional evaluation and drug screening of hCdOs. Furthermore, this approach is expected to support preclinical evaluation of drug efficacy and safety.