Fabrication and integration of partially-transparent ionic polymer–metal composite actuators into microphysiological systems

Abstract

We present partially-transparent ionic polymer–metal composite (IPMC) actuators and their seamless integration into microphysiological systems, to enable dynamic mechanical stimulation of cell monolayers with direct optical access. The proposed IPMC platform employs a layered microfabrication strategy that allows precise tailoring of electrode geometry while preserving optical transparency across selected regions of the actuator. This design overcomes a key limitation of conventional IPMCs, namely their inherent opacity and resulting lack of (bio-)opto-mechatronics compatibility, thereby facilitating in vitro applications and real-time optical and fluorescent microscopy. The actuators are integrated into standard 12-well culture plates through customized mechanical and electrical interfaces and are driven by a compact, programmable electronic control system, enabling flexible modulation of actuation dynamics within biologically-relevant regimes. We confirm the biocompatibility of the platform by culturing Human Embryonic Kidney (HEK) cells and contractile cardiomyocytes from human-induced pluripotent stem cells (hiPSC-CMs). Together, these advances establish a scalable, low-voltage, and optically-compatible actuation platform for organ-on-chip and mechanobiology applications.