Magnetic control devices and their biomedical applications: from untethered robotic intervention to precision nanomedicine

Externally applied magnetic fields offer a rare combination of properties for biomedical actuation: they penetrate biological tissue with minimal attenuation, interact with embedded materials without physical tethers, and lend themselves to real-time closed-loop control under clinical imaging.Over the past decade, magnetically controlled devices have evolved from proof-of-concept demonstrations to systems now under validation in large-animal and near-clinical settings [1].This progress spans millimeter-scale soft robots that swim, crawl, and grip inside the body, as well as nanoscale carriers that release therapeutic payloads on demand at a target site.A common thread is the integration of actuation, sensing, and drug-delivery functions directly into the material and structural design of the device, reducing reliance on external wiring or onboard electronics.The studies gathered in this special column reflect this trajectory, spanning device design, actuation strategy, and translational validation (Fig. 1).