When a person’s cornea – the transparent surface layer at the front of the eye – becomes damaged, it can be replaced using tissue from an organ donor. But there is a big shortage of corneal donors, as there are for every other type of organ.

An ideal solution would be to develop an artificial cornea, but is has proved very hard to design and manufacture a structure so that it is optically clear in the middle and biocompatible at the edges.

Now Garret Matthews, a biophysicist at the University of South Florida in Tampa, US, and his colleagues have come up with a design for artificial corneas that they say achieves this – using sea cucumbers.

Sea cucumbers are sausage-shaped echinoderms, most species of which live on the sea floor in a variety of marine environments around of the globe.

The team’s artificial cornea is made from tiny collagen fibres extracted from these sea cucumbers. When placed in a centrifuge, the fibres self assemble into layers in which the fibres are aligned vertically, a structure that is very similar to the tissue in mammalian corneas. The result is a thin layer of material that is transparent and biocompatible, as well as cheap and easy to make, says the team.