Abstract
Medical microrobotics capitalizes on smart materials to target specific body sites effectively, precisely and locally, thus holding promise to revolutionize precision medicine in the future. Advances in material science and microfabrication or nanofabrication techniques have facilitated the implementation of a myriad of functionalities into microrobots. Efficient navigation and monitoring of microrobots within the highly dynamic and often inaccessible environment of living mammalian tissues is paramount for their effective in vivo applications and eventual clinical translation. This need calls for the deployment of biomedical imaging modalities with adequate sensitivity, penetration depth and spatiotemporal resolution, as well as for efficient integration of biocompatible contrast materials into microrobots. In this Review, we discuss emerging approaches for multiplexed imaging and actuation of microrobots within complex biological environments, focusing on the synergistic combination of responsive and contrasting materials to achieve desired morphological and functional properties, in vivo visibility and biosafety. The convergence between microrobotics and biomedical imaging paves the way for a new generation of medical microrobots enabling the use of energy for both mechanical actuation and efficient monitoring of their activity in vivo.
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Acknowledgements
The authors acknowledge grant support from the Swiss National Science Foundation (310030_192757), US National Institutes of Health (RF1-NS126102), Innosuisse — Swiss Innovation Agency (51767.1 IP-LS), Swiss Cancer Research (KFS-5234-02-2021), Personalized Health and Related Technologies of the ETH Domain (PHRT-582), EU Joint Programme — Neurodegenerative Disease Research (JPND022-083), European Horizon RIA Digital and Emerging Technologies (101135053), European Horizon MSCA Doctoral Networks (101119924) and European Research Council (ERC) Advanced Grant SoMMoR project (grant no. 834531). P.W. and E.R. thank the Max Planck and ETH Center for Learning Systems (CLS) for financial support. The authors thank V.E. Fulford from Alar Illustration for her scientific illustrations.
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Wrede, P., Remlova, E., Chen, Y. et al. Synergistic integration of materials in medical microrobots for advanced imaging and actuation. Nat Rev Mater (2025). https://doi.org/10.1038/s41578-025-00811-4
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DOI: https://doi.org/10.1038/s41578-025-00811-4
