Scalable and stretchable 1D multifunctional fibers for multimodal sensing and stimulation

One-dimensional (1D) multifunctional fibers have garnered significant attention due to their advantageous geometry properties, which allows conformal interfacing with soft biological tissues and efficient charge transport. Here, we developed a solution-deposition strategy for the scalable and cost-effective fabrication of stretchable liquid metal fibers integrated with electrochemically stable, tissue-interfacing electrodes, thereby enabling the realization of stretchable multifunctional fibers. This fiber seamlessly combines electrodes and conductive pathways into a single structure, enabling versatile applications such as electrophysiological signal sensing, in vivo nerve stimulation, and wireless energy transmission. The multifunctional fiber demonstrates significantly improved electrical performance under strain, maintaining conductivity during stretching and bending, and exhibits lower impedance and higher signal stability, particularly during physiological monitoring and electrical stimulation. The fiber's excellent biocompatibility and mechanical compliance makes it well suited for wearable systems and long-term biomedical applications, offering a robust platform for next generation 1D bioelectronics.