Multifunctional Ferromagnetic Fiber Robots for Navigation, Sensing and Modulation in Biomedical Applications

Small-scale continuum robots capable of remotely active steering and navigation offer great potentials for biomedical applications. However, due to miniaturization and fabrication challenges, current continuum robots are often limited to millimeter or centimeter scales and hard to be integrated with multiple functionalities. Here, we present a sub-millimeter ferromagnetic fiber robotic platform for integrating navigation, sensing and modulation fabricated via a thermal drawing process. By using multiphysics modelling, tortuous blood vascular and agarose gel brain phantoms, we demonstrate that this fiber has the capability of navigating through minimally invasive cardiovascular surgery and neural probe insertion based on magnetic actuation. <i>In vitro</i> experiments establish the fiber robots’ functionalities of simultaneous irreversible electroporation ablation and chemical modulation. In a Langendorff-perfused mouse heart model, we show that the fiber catheter robots can achieve intracardiac electrogram monitoring, pacing and bioimpedance measurement. Furthermore, we demonstrate the ability of our fiber robots capturing brain activities with a single unit resolution and optically modulating brain activities using <i>in vivo</i> mouse models. Given their compact and multifunctionality, our ferromagnetic fiber robots have potentials to provide accessibility and treatment for previously inaccessible lesions, thereby improving surgical outcomes.