Irish Scientists Mimic Ancient Colour Secrets

More than 500 million years ago, nature developed an amazing way to create bright, shimmering colours. Tiny structures in feathers, wings, and shells reflect light in special ways to produce these colours. Scientists have been fascinated by this “structural colour” for a long time. Now, researchers at Trinity College Dublin have made a big step towards using this natural trick in new materials.

A team led by Professor Colm Delaney from Trinity’s School of Chemistry and AMBER, the Research Ireland Centre for Advanced Materials and BioEngineering Research, has found a new method to create and control structural colours. They used an advanced microfabrication technique inspired by nature.

This work is supported by a European Research Council Starting Grant and could be important for environmental sensors, medical diagnostics, and new light-based materials.

The key to their success was controlling how tiny particles called nanospheres arrange themselves. This is usually very hard to do. PhD student Teodora Faraone used a special high-resolution 3D printing method to carefully organise these nanospheres. This allows the material to reflect light and show all the colours of the rainbow in a controlled way.

Professor Delaney said this was the main challenge of the project. He is now on his way to Purdue University to present these findings at a major conference on microscale and nanoscale technology. He said, “We now have a way to fine-tune nanostructures to reflect bright, programmable colours.”

One exciting feature of the new material is how sensitive it is. The colours change when there are very small changes in the environment. This makes it useful for detecting chemicals and biological changes.

Dr Jing Qian, a postdoctoral researcher, used computer simulations to confirm the experimental results. This helped the team understand how the nanospheres organise themselves.

The researchers are now working on combining their colour control technique with materials that respond to their surroundings. They are developing tiny sensors that change colour in real time. These sensors are part of the IV-Lab Project, a European Innovation Council challenge led by the Italian Institute of Technology. One main goal is to create implantable devices that can monitor changes inside the human body.

Professor Delaney said collaboration was essential to the discovery. It was the teamwork between chemistry, materials science, and physics that made it possible to use a natural process that has been refined over millions of years. He also thanked fellow Trinity researchers Professors Larisa Florea and Louise Bradley for their contributions.

He added, “From ancient feathers to next-generation medical sensors, the future of colour is brighter and smaller than ever before.”