MRI-Guided Magnetic Micro/Nanorobots for Precision Neurotherapeutics: From Intelligent Navigation and BBB Penetration...

The rapid advancements in nanotechnology and medical imaging have positioned magnetic resonance imaging (MRI)-guided magnetic micro/nanorobots (MNRs) as a promising platform for integrated diagnosis and treatment of neurological diseases. This review highlights recent progress in MNR development, focusing on fabrication techniques, driving mechanisms, multimodal imaging integration, AI-enabled navigation, blood-brain barrier (BBB) penetration, and disease-specific applications. We analyze biomimetic designs and functional materials for MNRs, including pH- and ROS-responsive degradable materials, liquid metals, and multifunctional coatings.We further examine MRI-based navigation, emphasizing gradient and rotational field control, closed-loop kinematics, and MRI system compatibility. The review also explores AI-assisted multimodal imaging, including MRI, PET, photoacoustic, and fluorescence techniques, alongside the role of deep learning and digital twin models in real-time tracking and path optimization. In addressing the critical challenge of BBB penetration, we review both conventional and emerging strategies. Finally, we assess preclinical findings on the application of MNRs in brain tumors, cerebrovascular diseases, and neurodegenerative disorders. We further highlight how MNR systems improve therapeutic outcomes by enhancing local drug concentrations, enabling spatiotemporally controlled release, and providing real-time imaging feedback, thereby addressing key failure modes of conventional systemic therapies. The review concludes with a critical assessment of translational challenges and a roadmap toward intelligent, personalized neurotherapeutics.