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Du et al. Soft Sci 2024;4:35 https://dx.doi.org/10.20517/ss.2024.31 Page 19 of 23

Finally, the research trend in hydrogel actuators is shifting from single-stimulus responses to multi-stimulus
responses. Although multi-stimulus-responsive hydrogel actuators overcome some limitations of single
stimuli, they introduce additional complexity. It is necessary to consider the synergistic effects of multiple
stimuli, the reliability of these actuators, and the potential interference between different stimuli.

A promising future direction in this field is to create intelligent hydrogel actuators with robust performance,
multi-stimuli responsiveness, and precise, sustained release capabilities. These actuators may also
incorporate more sophisticated hardware such as physiological sensors, and more advanced software such
as artificial intelligence towards better automation and closed-loop therapy.

DECLARATIONS
Authors’ contributions
Supervised this work and provided guidance: Guan Y, Nan K
Contributed to the discussion and writing of this manuscript: Du N, Fan Y, Huang H, Guan Y, Nan K

Availability of data and materials
Not applicable.

Financial support and sponsorship
This work was supported by the National Natural Science Foundation of China (#21878262). Nan K
acknowledges start-up funding for the ZJU100 professorship from Zhejiang University.

Conflicts of interest
All authors declared that there are no conflicts of interest.

Ethical approval and consent to participate
Not applicable.

Consent for publication
Not applicable.

Copyright
© The Author(s) 2024.

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