This smart gel can create soft robots that, like octopuses, can walk under water and will not damage them even if they touch something. This smart gel can also produce human tissues such as artificial heart, stomach, and muscle. In addition, it can also diagnose diseases, detect and transport drugs, or equipment for performing underwater examinations.

This smart gel material is very soft, very flexible, cheaper than hard materials, and can be miniaturized. Devices made of soft materials are generally easier to design and control than hardware devices.

Researcher Howon Lee said: "In the field of biomedical engineering, smart gels for 3D printing have great potential because they are similar to human body tissues, they also contain a lot of moisture and are very soft. It can be used in many different types of underwater equipment. ."

In the 3D printing process, light is projected on the photosensitive solution and becomes a gel. Lee said that placing the hydrogel in a salty water solution (or electrolyte) triggers the movement of the gel through two thin wires: walking forward, turning, grabbing, and moving objects. Similar to humans walking about 1 inch tall.

The speed of smart gel movement can be controlled by changing the size of the gel. The gel can bend or change shape depending on the electric field. The gel is similar to a contracted muscle because it is made of a soft material, has a water content of more than 70%, and can respond to electrical stimuli.

"This study shows how 3D printing technology can expand the design and versatility of this smart gel," said Lee.

The study was published online at ACS Applied Materials and Interfaces.