Hydrogel interaction opens up the potential for biomedical applications and robots

Referring to robots, we often associate mechanical machines with metal. However, robots are also "soft" and this is an emerging field with many designs inspired by aquatic creatures such as octopus, squid or starfish. In May, researchers at the University of California created a hydrogel that could bend in near infrared laser light and today the University of North Carolina continues to improve the material with interactive hydrogels. electricity.

Technically called ionoprinting , the team in North Carolina uses a copper electrode to inject negatively charged ions into hydrogel material (Hydrogel is a highly absorbent polymer with 99 , 9% water). Copper ions bind to negatively charged ions in the hydrogel polymer's hydrogel chain, thereby creating a more mechanical structure.

Picture 1 of Hydrogel interaction opens up the potential for biomedical applications and robots
"Hands" by hydrogel robots

Then, when applying an electric current, the hydrogel becomes more flexible. The use of electric fields to stimulate the material is not new, but this is the first time that electro-mechanical electrodes have been used to control motion. In addition, this is the first time the bond between ions has been used to create a durable hydrogel network.

In addition to the ability to bend the hydrogel within a few seconds, the technology allows the use of moderate voltages to customize the mechanical properties of the hydrogel to produce exoskeleton strength. Copper ions can be injected into individual areas of the hydrogel material to create more accurate movement. If more ion is injected, the greater the bending capacity of the hydrogel.

Professor Orlin Velev, from the Department of Chemistry and Molecular Biotechnology at the University of North Carolina, said: "We are currently planning to use this technique to develop microstructure devices with motor structure. " Technology not only brings great potential for the soft robot sector but also many biomedical applications. Artificial sensors, intelligent environmental sensors, actuators, microbiology robots, cellular frameworks and drug delivery devices are some of the potential uses for technology, according to the researchers. .