Shape-changing hydrogel opens research possibilities for flexible devices

Taking inspiration from slow changes in living tissue

Researchers led by Du Xuemin at the Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, have developed a hydrogel system inspired by the way living organisms change shape over time. The work concerns a material that can evolve gradually, rather than only reacting with a rapid, one-off movement.

The system is known as STERS, short for spatiotemporally evolving reactive species. The study explores how chemical activity distributed through space and time can be used to control a material’s changing form. Calling the behaviour life-like describes that inspiration; the hydrogel is not a living organism.

Light initiates a chemical process

The approach combines liquid-metal particles with a hydrogel environment and uses near-infrared light as a trigger. Chemical processes inside the material then support changes that unfold over a longer period. This differs from designs in which movement depends only on an immediate response to a continuously applied external stimulus.

The research describes shape evolution over timescales from minutes to weeks. Managing that timescale matters because biological growth and tissue adaptation do not necessarily happen as fast as the motion of a conventional responsive material. A material that changes more slowly could offer a different starting point for designing interfaces with soft or growing structures.

Possible uses in biomedical engineering

The supplied article discusses tissue-engineering scaffolds and flexible interfaces as potential areas of interest. A scaffold provides a structure on which cells can grow. Researchers developing such systems must consider how the supporting material behaves as the surrounding biological environment changes.

Brain-computer interfaces and other soft biomedical devices are also presented as possible future research directions. The development should not be treated as confirmation that a clinical implant based on this technology has been approved or is ready for routine use. Those applications would require their own testing and validation.

A research direction for soft robotics

Gradual, programmable changes in form may also be useful when investigating soft robotic components and artificial-muscle concepts. The aim in such work is to move beyond rigid mechanisms and explore materials that can adapt their shape in a controlled manner.

For now, the important result is a new way to investigate time-dependent changes in a hydrogel. Ideas involving future wearable electronics, adaptive devices or soft robots remain possible applications to explore. They are not guaranteed products or evidence that devices can already grow inside the human body.

Reporting: Erkan Veyseloğlu