DNA Sunscreen Gets Better, Not Weaker, Over Time – Scientific American

Many sunscreens wear off over the course of a day, but a DNA material developed by US scientists gets better at absorbing ultraviolet (UV) light the longer it is exposed to it.1The transparent coating could protect skin particularly damaged areas from sunburn over long periods of time.

UV light is particularly bad for wounds because the skin is already weakened, explainsClara Piccirilloa materials chemist from the Portuguese Catholic University, whopreviously developed a fishbone-derived sunscreenbut wasnt involved in this study. There is a lot of research to try and find multifunctional materials for dressings, for instance something antibacterial that at the same time protects from UV light.

To do this,Guy Germanfrom Binghamton University and his colleagues looked to one of the most common polymers on the planet: DNA. The team had already established that self-assembled DNA films could absorb UV light. But what was really interesting is that the more UV we dosed the films with, the better they got at attenuating the light, German says.

This unexpected behaviour is likely to be the result of hyperchromicity: when exposed to UV light, the DNAs strands separate and unravel. New bonds between the DNA chains and changes in the materials crystal structure then increase its ability to absorb and scatter light.

The coating is transparent to visible light, which would make it particularly suitable as a wound covering. You wouldnt need to lift up a wound covering as this might not be a good idea in hostile or contaminated environments, explains German. Moreover, the DNA film keeps the skin hydrated, which has been shown to promote faster healing.2Another advantage is that its made out of DNA, something that we already have in our bodies, so its likely that its not toxic, says Piccirillo. The material is currently undergoing biological testing, German adds.

As to whether the material could also work as an everyday sunscreen, German hopes so. A DNA-based cream could curbworries about the safety of common UV protectantsand decrease the amount ofcoral-harming chemicals released into coastal watersby sunscreen wearers.

However, in its current film-like form the material cant be made introduced into a cream, which requires compounds to be soluble or finely dispersed. It is the formation of the film that offers UV protection, says Piccirillo. I cant see this applied in an emulsion in its current form though that doesnt mean that in the future theyll find a way to formulate it that way.

We have lots of testing and work to do to push it forward to commercialisation status, acknowledges German, but thats another pathway that we are exploring.

This article is reproduced with permission fromChemistry World. The article wasfirst publishedon August 2, 2017.

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DNA Sunscreen Gets Better, Not Weaker, Over Time - Scientific American