Magnetic soft robots in medicine: material and structural designs for organ-specific applications

Magnetic soft robots are emerging as biomedical tools for minimally invasive interventions. They synergize remote magnetic actuation with the compliance of soft materials to ensure safe navigation and therapy within delicate anatomical structures, such as the gastrointestinal tract, blood vessels, and urinary system. This review analyzes material-tissue toxicity and mechanical interactions and summarizes material innovations in magnetic hydrogels, elastomers, ferrofluids, and responsive composites. Organ-specific material and structural designs for clinical applications are discussed, showcasing advances of soft medical robots in targeted drug delivery, thrombus extraction, tissue sampling, thermal therapy, and in situ sensing. Furthermore, we focus on key translational challenges, including long-term biostability of materials, adaptive closed-loop control, and multifunctional system integration, which must be addressed to reach the full potential of magnetic soft robots for clinical applications.