Flytrap Inspired pH‐Driven 3D Hydrogel Actuator by Femtosecond Laser Microfabrication

With the development of bionics and nanophotonics, hydrogel microactuators capable of responding to external stimuli to produce controllable deformations have attracted a great deal of interest. These microactuators hold significant promise in areas such as bionic devices, soft robotics, and precision sensors. It is not a trivial task to make such small devices as well as to make them work in a controlled manner. Here, inspired by the intelligent response of flytrap, a smart hydrogel microactuator based on a bionic asymmetric structure is demonstrated. The designed asymmetric microstructure is fabricated by femtosecond laser direct writing with deformation time of 1.2 s and recovery time of 0.3 s. The grasping and releasing behavior of the microactuator for micro‐objects can be realized and tuned by using pH‐triggered shape changes, demonstrating its potential for applications, such as flexible robotics, smart sensors, and microscopic manipulation. Smart asymmetric hydrogel microactuators inspired by flytrap were prepared by femtosecond laser direct writing technology. The controllable grasping and releasing of single and multiple microspheres are realized by tuning the responsive properties of the microactuators. This protocol can inspire the development of hydrogel microactuators and hold promise for applications in micro‐robotics, smart sensing, and biomedicine.