Dual-photoresponsive elastomer nanofibres enhanced myofibre hybrid for skeletal muscle actuation

Abstract Light-responsive polymers hold great promise for remote or battery-free actuation in soft robotics. Yet, current systems often suffer from limited responsiveness, processability and biocompatibility—challenges that are particularly critical for muscle restoration applications. Here, we introduce MyoHybrid, a ‘dual-photoresponsive’ skeletal muscle actuator combining optogenetic myofibres with a scalable, unidirectionally aligned polyurethane–azobenzene (PAzo) nanofibre scaffold. The term ‘dual-photoresponsive’ refers to the synergy between intrinsic PAzo photoactuation—driven by coupled photochemical and photothermal effects—and optogenetically induced myofibre contractions. This anisotropic integration enables cooperative light-driven actuation of both nanofibres and myotubes. Compared with PAzo flat solid substrate, aligned PAzo nanofibres improved unidirectional myotube fusion by 25.3% and enhanced maturation by 37.7%. Furthermore, optogenetic stimulation of the resulting myofibres led to a 60% increase in contraction velocity and force relative to glass controls. MyoHybrid established a seamless interface between synthetic nanofibres and biological myofibres, offering a programmable platform for muscle-on-chip models, biohybrid actuators and light-driven soft tissue systems. This work bridges mechanical bionics and cellular actuation, advancing next-generation soft robotics and regenerative technologies.