Multifunctional Fiber Robotics with Low Mechanical Hysteresis for Magnetic Navigation and Inhaled Gas Sensing.

Recently, increasing research attention has been directed toward detecting the distribution of hazardous gases in the respiratory system for potential diagnosis and treatment of lung injury. Among various technologies, magnetic fiber robots exhibit great potential for minimally invasive surgery and in situ disease diagnosis. However, integrating magnetic fibers with functionalized sensitive materials remains challenging while preserving the miniaturized fibers' mechanical properties. Herein, we report TiCT/TPU/NdFeB fibers prepared by facile wet spinning, spray coating, and magnetization, obtaining fibers with decent strength (4.34 MPa) and low hysteresis while maintaining mechanical robustness and magnetoelectric properties. Such fiber robotics could be magnetically actuated for complex movement, while the surface-coated MXene endowed them with the specific response of 5.2% to 40 ppm of triethylamine gas. Fiber robotics realized magnetically driven omnidirectional steering and navigation for propulsion in tubular environments by combination with nitinol guide wires. Consequently, based on magnetic navigation and the chemiresistive gas response, the proposed fiber robotics could locate the position with the highest level of the triethylamine gas inside a bronchial model and provide information on its distribution. This provides a proof-of-concept demonstration for inhaled hazardous gas detection and minimally invasive robotic surgery by multifunctional fiber robotics.