Toward intelligent micro/nanorobots for biomedical applications

Micro/nanorobots (MNRs) have emerged as versatile microscale platforms for precise tasks in complex biological environments, enabled by advances in microfabrication, smart materials, and multiscale actuation. Despite progress, most MNRs remain heavily dependent on external control and show limited adaptability under dynamic, heterogeneous in vivo conditions. These limitations have motivated the development of intelligent micro/nanorobots, integrating responsiveness across structure, materials, motion, and functional application. This review presents a framework for intelligent MNRs along three interconnected dimensions. Structural and material intelligence, via geometry, multistability, and stimuli-responsive materials, enables intrinsic adaptability and environment-responsive behaviors. Motion and navigation intelligence, encompassing multimodal locomotion, imaging-guided control, swarm coordination, and AI-assisted strategies, supports robust, autonomous operation under physiological complexity. Applications of intelligent MNRs facilitate context-aware drug delivery, adaptive therapeutic interventions, real-time sensing, and microenvironment modulation, enabling functionally integrated performance. By synthesizing advances across these domains, we highlight intelligent MNRs as a central strategy for bridging laboratory demonstrations and clinical translation. Key challenges and future directions include integrated intelligence architectures, improved biocompatibility and manufacturability, and rigorous in vivo validation. Collectively, intelligent MNRs hold the potential to evolve into adaptive, safe, and semi-autonomous microscale systems for precise biomedical operation.