Scientists at Binghamton University in New York have developed a film from the DNA of salmon which gets better at protecting the skin from ultraviolet light the more it is exposed to the Sun.

It also helps lock in moisture beneath the surface which is usually lost during tanning. The film was made from a mixture of the DNA from salmon sperm, water and ethanol to create sheets of a transparent crystalline material.

They found that the more they exposed the film to UV light, the better the film got at absorbing it. The DNA coating can also store and hold water much more than uncoated skin. When applied to human skin, they are capable of slowing water evaporation and keeping the tissue hydrated for extended periods of time.

The team also wants to test whether the material could also be useful as a wound covering. Because it is transparent, doctors would be able to monitor how well a wound was healing without removing the dressing.