Micro/nanorobot physical stimulation: from mechanisms to precision therapeutics

Micro/nanorobots (MNRs) exhibit remarkable potential for precise manipulation at cellular and subcellular scales. By enabling targeted navigation under external field guidance, intelligent MNR actuators overcome the inherent spatiotemporal limitations of conventional drug delivery systems, allowing direct access to specific biological sites. Leveraging synergistic actuation modalities-including magnetic, acoustic, and optical fields-MNRs can deliver localized physical stimuli in situ, thereby dynamically modulating cellular behaviors through mechanisms such as mechanical forces, electrical signaling, and thermal effects. This review systematically delineates the fundamental principles governing MNR-mediated regulation of cellular physiological activities under diverse physical stimulation strategies. Particular emphasis is placed on their applications in modulating synaptic plasticity within the nervous system, promoting tissue regeneration in regenerative medicine, and intervening in pathological processes within the tumor microenvironment. Furthermore, a comparative analysis of existing stimulation modalities is presented, alongside a critical evaluation of current challenges and future perspectives, with the aim of guiding the continued development of MNR-based technologies in biomedicine.