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Small-scale robots, ranging in size from micrometers to centimeters, have gained significant attention in the biomedical field. However, conventional small-scale robots made of rigid materials encounter challenges in adapting themselves to the soft tissues and complicated environments of human body. Compared to the rigid counterpart, small-scale hydrogel-based robots hold great promises due to their tissue-like low modulus, outstanding biocompatibility and accessible stimuli-responsive capabilities. These attributes offer small-scale hydrogel-based robots with multimodal locomotion and reinforced functions, further enhancing the adaptability in manipulation and tasks execution for various biomedical applications. In this review, we present recent advances in small-scale hydrogel-based robots. We first summarize the design principles of small-scale hydrogel-based robots including materials, fabrication techniques and manipulation strategies, then highlighting their upgraded functions and adaptive biomedical applications. Finally, we discuss existing challenges and future perspectives for small-scale hydrogel-based robots.

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Recent advances in small-scale hydrogel-based robots for adaptive biomedical applications

Show Author's information Mingzhe NieQilong ZhaoXuemin Du( )
Institute of Biomedical & Health Engineering, Shenzhen Institute of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, China


Small-scale robots, ranging in size from micrometers to centimeters, have gained significant attention in the biomedical field. However, conventional small-scale robots made of rigid materials encounter challenges in adapting themselves to the soft tissues and complicated environments of human body. Compared to the rigid counterpart, small-scale hydrogel-based robots hold great promises due to their tissue-like low modulus, outstanding biocompatibility and accessible stimuli-responsive capabilities. These attributes offer small-scale hydrogel-based robots with multimodal locomotion and reinforced functions, further enhancing the adaptability in manipulation and tasks execution for various biomedical applications. In this review, we present recent advances in small-scale hydrogel-based robots. We first summarize the design principles of small-scale hydrogel-based robots including materials, fabrication techniques and manipulation strategies, then highlighting their upgraded functions and adaptive biomedical applications. Finally, we discuss existing challenges and future perspectives for small-scale hydrogel-based robots.

Keywords: hydrogel, multi-function, locomotion, adaptability, small-scale robot



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Publication history

Publication history

Received: 25 June 2023
Revised: 07 September 2023
Accepted: 11 September 2023
Published: 16 October 2023
Issue date: February 2024


© Tsinghua University Press 2023



The authors acknowledge the financial support provided by the National Natural Science Foundation of China (Nos. 52022102, and 52261160380), National Key R&D Program of China (No. 2017YFA0701303), the Youth Innovation Promotion Association of CAS (No. 2019353), Guangdong Regional Joint Fund-Key Project (No. 2021B1515120076), and the Fundamental Research Program of Shenzhen (Nos. RCJC20221008092729033, and JCYJ20220818101800001).