Out-Of-Equilibrium Hydrogel Microrobots Exhibiting Autonomous Deformation, Controllable Autolysis, and Directed...

Area of Science:

• Soft Robotics
• Materials Science
• Biomedical Engineering

Background:

• Developing microrobots with multiple integrated functions is crucial for complex applications.
• Existing microrobots often lack adaptability and autonomous control in response to stimuli.

Purpose of the Study:

• To engineer hydrogel microrobots with autonomous deformation, controllable disintegration, and directed locomotion.
• To demonstrate the utility of these microrobots in navigating confined spaces and delivering cargo.

Main Methods:

• Hydrogel microrobots were synthesized by crosslinking carboxyl-decorated polymers via coumarin dimerization.
• Autonomous swelling/shrinking was achieved by chemical fuel-induced conversion of carboxyl groups to anhydrides and subsequent hydrolysis.
• Controllable disintegration was enabled by photocleavage of coumarin dimers, and directed locomotion by incorporating magnetic powders for magnetic field guidance.

Main Results:

• Microrobots exhibited autonomous size changes in response to a chemical fuel (carbodiimide).
• Rapid disintegration (<10 min) was achieved upon UV irradiation.
• Magnetic guidance allowed for controlled movement and navigation through narrow terrains.
• Successful cargo release at a target location was demonstrated.

Conclusions:

• The developed hydrogel microrobots possess integrated functions for adaptive locomotion and targeted cargo delivery.
• This technology holds promise for advancing precision drug delivery and non-invasive therapies.
• The lifelike, adaptable nature of these soft robots opens new avenues in complex robotic applications.