![3d printing of light activated hydrogel actuators](https://utterbuzz.com/wp-content/uploads/2024/07/3d-printing-of-light-activated-hydrogel-actuators-640x360.jpg)
An international team of researchers has embedded gold nanorods in hydrogels that can be processed through 3D printing to create structures that contract when exposed to light — and expand again when the light is removed. Because this expansion and contraction can be performed repeatedly, the 3D-printed structures can serve as remotely controlled actuators.