Tag Archives: sunscreen

DNA sunscreen: the longer you wear it, the better it gets due to its sacrificial skin

Using this new sunscreen does mean slathering on salmon sperm, more or lees, (read the Methods section of the academic paper cited later in this post). Considering that you’ve likely eaten (insect parts in chocolate) and slathered on more discomfiting stuff already and this development gives you access to an all natural, highly effective sunscreen, if it ever makes its way out of the laboratory, it might not be so bad. From a July 26, 2017 article by Sarah Knapton for The Telegraph,

Sunscreen made from DNA [deoxyribonucleic acid] which acts like a second skin to prevent sun damage is on the horizon.

Scientists in the US 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.

Exciting, yes? A July 27, 2017 Binghamton University news release (also on EurekAlert but dated July 26, 2017) provides more detail,

“Ultraviolet (UV) light can actually damage DNA, and that’s not good for the skin,” said Guy German, assistant professor of biomedical engineering at Binghamton University. “We thought, let’s flip it. What happens instead if we actually used DNA as a sacrificial layer? So instead of damaging DNA within the skin, we damage a layer on top of the skin.”

German and a team of researchers developed thin and optically transparent crystalline DNA films and irradiated them with UV light. They found that the more they exposed the film to UV light, the better the film got at absorbing it.

“If you translate that, it means to me that if you use this as a topical cream or sunscreen, the longer that you stay out on the beach, the better it gets at being a sunscreen,” said German.

As an added bonus, the DNA coatings are also hygroscopic, meaning that skin coated with the DNA films can 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.

German intends to see next if these materials might be good as a wound covering for hostile environments where 1) you want to be able to see the wound healing without removing the dressing, 2) you want to protect the wound from the sun and 3) you want to keep the wound in a moist environment, known to promote faster wound healing rates.

“Not only do we think this might have applications for sunscreen and moisturizers directly, but if it’s optically transparent and prevents tissue damage from the sun and it’s good at keeping the skin hydrated, we think this might be potentially exploitable as a wound covering for extreme environments,” he said.

Here’s a link to and a citation for the paper,

Non-ionising UV light increases the optical density of hygroscopic self assembled DNA crystal films by Alexandria E. Gasperini, Susy Sanchez, Amber L. Doiron, Mark Lyles & Guy K. German. Scientific Reports 7, Article number: 6631 (2017) doi:10.1038/s41598-017-06884-8 Published online: 26 July 2017

This paper is open access.

The ultimate natural sunscreen

For those of us in the northern hemisphere, sunscreen season is on the horizon. While the “ultimate natural sunscreen” researchers from the University of California at San Diego (UCSD) have developed is a long way from the marketplace, this is encouraging news (from a May 17, 2017 news item on Nanowerk),

Chemists, materials scientists and nanoengineers at UC San Diego have created what may be the ultimate natural sunscreen.

In a paper published in the American Chemical Society journal ACS Central Science, they report the development of nanoparticles that mimic the behavior of natural melanosomes, melanin-producing cell structures that protect our skin, eyes and other tissues from the harmful effects of ultraviolet radiation.

“Basically, we succeeded in making a synthetic version of the nanoparticles that our skin uses to produce and store melanin and demonstrated in experiments in skin cells that they mimic the behavior of natural melanosomes,” said Nathan Gianneschi, a professor of chemistry and biochemistry, materials science and engineering and nanoengineering at UC San Diego, who headed the team of researchers. The achievement has practical applications.

A May 17, 2017 UCSD news release, which originated the news item, delves into the research,

“Defects in melanin production in humans can cause diseases such as vitiligo and albinism that lack effective treatments,” Gianneschi added.

Vitiligo develops when the immune system wrongly attempts to clear normal melanocytes from the skin, effectively stopping the production of melanocytes. Albinism is due to genetic defects that lead to either the absence or a chemical defect in tyrosinase, a copper-containing enzyme involved in the production of melanin. Both of these diseases lack effective treatments and result in a significant risk of skin cancer for patients.

“The widespread prevalence of these melanin-related diseases and an increasing interest in the performance of various polymeric materials related to melanin prompted us to look for novel synthetic routes for preparing melanin-like materials,” Gianneschi said.

UC San Diego Ultimate natural sunscreenThe scientists found that the synthetic nanoparticles were taken up in tissue culture by keratinocytes, the predominant cell type found in the epidermis, the outer layer of skin. Photo by Yuran Huang and Ying Jones/UC San Diego

Melanin particles are produced naturally in many different sizes and shapes by animals—for iridescent feathers in birds or the pigmented eyes and skin of some reptiles. But scientists have discovered that extracting melanins from natural sources is a difficult and potentially more complex process than producing them synthetically.

Gianneschi and his team discovered two years ago that synthetic melanin-like nanoparticles could be developed in a precisely controllable manner to mimic the performance of natural melanins used in bird feathers.

“We hypothesized that synthetic melanin-like nanoparticles would mimic naturally occurring melanosomes and be taken up by keratinocytes, the predominant cell type found in the epidermis, the outer layer of skin,” said Gianneschi.

In healthy humans, melanin is delivered to keratinocytes in the skin after being excreted as melanosomes from melanocytes.

The UC San Diego scientists prepared melanin-like nanoparticles through the spontaneous oxidation of dopamine—developing biocompatible, synthetic analogues of naturally occurring melanosomes. Then they studied their update, transport, distribution and ultraviolet radiation-protective capabilities in human keratinocytes in tissue culture.

The researchers found that these synthetic nanoparticles were not only taken up and distributed normally, like natural melanosomes, within the keratinocytes, they protected the skin cells from DNA damage due to ultraviolet radiation.

“Considering limitations in the treatment of melanin-defective related diseases and the biocompatibility of these synthetic melanin-like nanoparticles in terms of uptake and degradation, these systems have potential as artificial melanosomes for the development of novel therapies, possibly supplementing the biological functions of natural melanins,” the researchers said in their paper.

The other co-authors of the study were Yuran Huang and Ziying Hu of UC San Diego’s Materials Science and Engineering Program, Yiwen Li and Maria Proetto of the Department of Chemistry and Biochemistry; Xiujun Yue of the Department of Nanoengineering; and Ying Jones of the Electron Microscopy Core Facility.

The UC San Diego Office of Innovation and Commercialization has filed a patent application on the use of polydopamine-based artificial melanins as an intracellular UV-shield. Companies interested in commercializing this invention should contact Skip Cynar at invent@ucsd.edu

Here’s a link to and a citation fro the paper,

Mimicking Melanosomes: Polydopamine Nanoparticles as Artificial Microparasols by
Yuran Huang, Yiwen Li, Ziying Hu, Xiujun Yue, Maria T. Proetto, Ying Jones, and Nathan C. Gianneschi. ACS Cent. Sci., Article ASAP DOI: 10.1021/acscentsci.6b00230 Publication Date (Web): May 18, 2017

Copyright © 2017 American Chemical Society

This is an open access paper,

Effective sunscreens from nature

The dream is to find sunscreens that don’t endanger humans or pollute the environment and it seems that Spanish scientists may have taken a step closer to making that dream a reality (from a Jan. 30, 2017 Wiley Publications press release (also on EurekAlert),

The ideal sunscreen should block UVB and UVA radiation while being safe and stable. In the journal Angewandte Chemie, Spanish scientists have introduced a new family of UVA and UVB filters based on natural sunscreen substances found in algae and cyanobacteria. They are highly stable and enhance the effectivity [sic] of commercial sunscreens.

Good news for sunseekers. Commercial [sic] available sunscreen lotions can very effectively protect from dangerous radiation in the ultraviolet [spectrum], but they need to be applied regularly and in high amounts to develop their full potential. One of the most critical issues is the limited stability of the UV filter molecules. Inspired by nature, Diego Sampedro and his colleagues from La Rioja University in Logrono and collaborators from Malaga University and Alcala University, Madrid, Spain, have screened a natural class of UV-protecting [blocking?] molecules for their possible use in skin protection. They adjusted the nature-given motif [sic] to the requirements of chemical synthesis and found that the molecules could indeed boost the sun protection factor of common formulations.

The natural sunscreen molecules are called microsporine-like amino acids (MAAs) and are widespread in the microbial world, most prominently in marine algae and cyanobacteria. MAAs are small molecules derived from amino acids, thermally stable, and they absorb light in the ultraviolet region, protecting the microbial DNA from radiation damage. Thus they are natural sunscreens, which inspired Sampedro and his colleagues to create [a] new class of organic sunscreen compounds.

Theoretical calculations revealed what is chemically needed for a successful design. “We performed a computer calculation of several basic scaffolds [..] to identify the simplest compound that fulfills the requisites for efficient sunscreens”, the authors write. The result of their search was a set of molecules which were readily synthesized, “avoiding the decorating substituents that come from the biosynthetic route.” Thus the small basic molecules can be tuned to give them more favorable properties.

The authors found that the synthesized compounds are characterized by excellent filter capacities in the relevant UV range. In addition they are photostable, much more than, for example, oxybenzene [sic] which is a widely used sunscreen in commercial formulations. They do not react chemically and dissipate radiation as heat (but not to such an extent that the skin temperature would rise as well). And, most importantly, when tested in real formulations, the sun protection factor (SPF) rose by a factor of more than two. Thus they could be promising targets for more stable, more efficient sunscreen lotions. Good news for your next summer vacation.

There’s some unusual phrasing so, I’m guessing that the writer it not accustomed to writing press releases in English. One other comment, it’s oxybenzone that’s often used as an ingredient in commercial sunscreens.

Here’s a link to and a citation for the paper,

Rational Design and Synthesis of Efficient Sunscreens To Boost the Solar Protection Factor by Raúl Losantos, Ignacio Funes-Ardoiz, Dr. José Aguilera, Prof. Enrique Herrera-Ceballos, Dr. Cristina García-Iriepa, Prof. Pedro J. Campos, and Diego Sampedro. Angewandte Chemie International Edition Volume 56, Issue 10, pages 2632–2635, March 1, 2017 DOI: 10.1002/anie.201611627 Version of Record online: 27 JAN 2017

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.

I have previously featured work on another natural sunscreen. In that case it was to be derived from English ivy (July 22, 2010 posting); there was an update on the English ivy work in a May 30, 2016 posting but the researcher has moved in a different direction looking at wound healing and armour as possible applications for the research.

Watching paint dry at the nanoscale

When paint dries it separates itself into two layers and according to scientists this may have implications for improving performance in products ranging from paints to beauty and cosmetics. From a March 18, 2016 news item on ScienceDaily,

New research published today in the journal Physical Review Letters has described a new physical mechanism that separates particles according to their size during the drying of wet coatings. The discovery could help improve the performance of a wide variety of everyday goods, from paint to sunscreen.

A March 18, 2016 University of Surrey (England) press release (also on EurekAlert), which originated the news item, provides more details,

Researchers from the University of Surrey [England, UK] in collaboration with the Université Claude Bernard, Lyon [France] used computer simulation and materials experiments to show how when coatings with different sized particles, such as paints dry, the coating spontaneously forms two layers.

This mechanism can be used to control the properties at the top and bottom of coatings independently, which could help increase performance of coatings across industries as diverse as beauty and pharmaceuticals.

Dr Andrea Fortini, of the University of Surrey and lead author explained:

“When coatings such as paint, ink or even outer layers on tablets are made, they work by spreading a liquid containing solid particles onto a surface, and allowing the liquid to evaporate. This is nothing new, but what is exciting is that we’ve shown that during evaporation, the small particles push away the larger ones, remaining at the top surface whilst the larger are pushed to bottom. This happens naturally.”

Dr Fortini continued, “This type of ‘self-layering’ in a coating could be very useful. For example, in a sun screen, most of the sunlight-blocking particles could be designed to push their way to the top, leaving particles that can adhere to the skin near the bottom of the coating. Typically the particles used in coatings have sizes that are 1000 times smaller than the width of a human hair so engineering these coatings takes place at a microscopic level. ”

The team is continuing to work on such research to understand how to control the width of the layer by changing the type and amount of small particles in the coating and explore their use in industrial products such as paints, inks, and adhesives

Here’s a link to and a citation for the paper,

Dynamic Stratification in Drying Films of Colloidal Mixtures by Andrea Fortini, Ignacio Martín-Fabiani, Jennifer Lesage De La Haye, Pierre-Yves Dugas, Muriel Lansalot, Franck D’Agosto, Elodie Bourgeat-Lami, Joseph L. Keddie, and Richard P. Sear. Phys. Rev. Lett. 116, 118301 – Published 18 March 2016 DOI:http://dx.doi.org/10.1103/PhysRevLett.116.118301

© 2016 American Physical Society

This article is behind a paywall.

Finding a way to prevent sunscreens from penetrating the skin

While nanosunscreens have been singled out for their possible impact on our health, the fact is many sunscreens contain dangerous ingredients penetrating the skin. A Dec. 14, 2015 news item on ScienceDaily describes some research into getting sunscreens to stay on the skin surface avoiding penetration,

A new sunscreen has been developed that encapsulates the UV-blocking compounds inside bio-adhesive nanoparticles, which adhere to the skin well, but do not penetrate beyond the skin’s surface. These properties resulted in highly effective UV protection in a mouse model, without the adverse effects observed with commercial sunscreens, including penetration into the bloodstream and generation of reactive oxygen species, which can damage DNA and lead to cancer.

A US National Institute of Biomedical Imaging and Bioengineering (NIBIB) Dec. 14, 2015 news release, which originated the news item, expands on the theme (Note: Links have been removed),

Commercial sunscreens use compounds that effectively filter out damaging UV light. However, there is concern that these agents have a variety of harmful effects due to penetration past the surface skin. For example, these products have been found in human breast tissue and urine and are known to disrupt the normal function of some hormones. Also, the exposure of the UV filters to light can produce toxic reactive oxygen species that are destructive to cells and tissues and can cause tumors through DNA damage.

“This work applies a novel bioengineering idea to a little known but significant health problem, adds Jessica Tucker, Ph.D., Director of the NIBIB Program in Delivery Systems and Devices for Drugs and Biologics. “While we are all familiar with the benefits of sunscreen, the potential toxicities from sunscreen due to penetration into the body and creation of DNA-damaging agents are not well known. Bioengineering sunscreen to inhibit penetration and keep any DNA-damaging compounds isolated in the nanoparticle and away from the skin is a great example of how a sophisticated technology can be used to solve a problem affecting the health of millions of people.”

Bioengineers and dermatologists at Yale University in New Haven, Connecticut combined their expertise in nanoparticle-based drug delivery and the molecular and cellular characteristics of the skin to address these potential health hazards of current commercial sunscreens.

The news release then goes on to provide some technical details,

The group encapsulated a commonly used sunscreen, padimate O (PO), inside a nanoparticle (a very small molecule often used to transport drugs and other agents into the body). PO is related to the better-known sunscreen PABA.

The bioadhesive nanoparticle containing the sunscreen PO was tested on pigs for penetration into the skin. A control group of pigs received the PO alone, not encapsulated in a nanoparticle. The PO penetrated beyond the surface layers of skin where it could potentially enter the bloodstream through blood vessels that are in the deeper skin layers. However, the PO inside the nanoparticle remained on the surface of the skin and did not penetrate into deeper layers.

Because the bioadhesive nanoparticles, or BNPs are larger than skin pores it was somewhat expected that they could not enter the body by that route. However, skin is full of hair follicles that are larger than BNPs and so could be a way for migration into the body. Surprisingly, BNPs did not pass through the hair follicle openings either. Tests indicated that the adhesive properties of the BNPs caused them to stick to the skin surface, unable to move through the hair follicles.

Further testing showed that the BNPs were water resistant and remained on the skin for a day or more, yet were easily removed by towel wiping. They also disappeared in several days through natural exfoliation of the surface skin.

BNPs enhance the effect of sunscreen

An important test was whether the BNP-encapsulated sunscreen retained its UV filtering properties. The researchers used a mouse model to test whether PO blocked sunburn when encapsulated in the BNPs. The BNP formulation successfully provided the same amount of UV protection as the commercial products applied directly to the skin of the hairless mouse model. Surprisingly, this was achieved even though the BNPs carried only a fraction (5%) of the amount of commercial sunblock applied to the mice.

Finally, the encapsulated sunscreen was tested for the formation of damaging oxygen-carrying molecules known as reactive oxygen species, (ROS) when exposed to UV light. The researchers hypothesized that any ROS created by the sunscreen’s interaction with UV would stay contained inside the BNP, unable to damage surrounding tissue. Following exposure to UV light, no damaging ROS were detected outside of the nanoparticle, indicating that any harmful agents that were formed remained inside of the nanoparticle, unable to make contact with the skin.

“We are extremely pleased with the properties and performance of our BNP formulation,” says senior author Mark Saltzman, Ph.D., Yale School of Engineering and Applied Science. “The sunscreen loaded BNPs combine the best properties of an effective sunscreen with a safety profile that alleviates the potential toxicities of the actual sunscreen product because it is encapsulated and literally never touches the skin.” Adds co-senior author, Michael Girardi, M.D. “Our nanoparticles performed as expected, however, these are preclinical findings. We are now in a position to assess the effects on human skin.”

So, all of this work has been done on animal models, which means that human clinical trials are the likely next step. As we wait, here’s a link to and a citation for this group’s paper,

A sunblock based on bioadhesive nanoparticles by Yang Deng, Asiri Ediriwickrema, Fan Yang, Julia Lewis, Michael Girardi, & W. Mark Saltzman. Nature Materials 14, 1278–1285 (2015) doi:10.1038/nmat4422 Published online 28 September 2015

This paper is behind a paywall.

Safer sunblock and bioadhesive nanoparticles from Yale University

The skin has a lot of protective barriers but it’s always possible to make something better so a sunblock that doesn’t penetrate the* skin at all seems like it might be a good thing. Interestingly, this new sunblock or sunscreen is enabled by nanoparticles but not the metallic nanoparticles found in what are sometimes called nanosunscreens. From a Sept. 29, 2015 news item on Nanowerk,

Researchers at Yale have developed a sunscreen that doesn’t penetrate the skin, eliminating serious health concerns associated with commercial sunscreens.

Most commercial sunblocks are good at preventing sunburn, but they can go below the skin’s surface and enter the bloodstream. As a result, they pose possible hormonal side effects and could even be promoting the kind of skin cancers they’re designed to prevent.

But researchers at Yale have developed a new sunblock, made with bioadhesive nanoparticles, that stays on the surface of the skin.

A Sept. 28, 2015 Yale University news release by William Weir, whch originated the news item, describes the research in more detail,

“We found that when we apply the sunblock to the skin, it doesn’t come off, and more importantly, it doesn’t penetrate any further into the skin,” said the paper’s senior author, Mark Saltzman, the Goizueta Foundation Professor of Biomedical Engineering. “Nanoparticles are large enough to keep from going through the skin’s surface, and our nanoparticles are so adhesive that they don’t even go into hair follicles, which are relatively open.”

Using mouse models, the researchers tested their sunblock against direct ultraviolet rays and their ability to cause sunburn. In this regard, even though it used a significantly smaller amount of the active ingredient than commercial sunscreens, the researchers’ formulation protected equally well against sunburn.

They also looked at an indirect — and much less studied — effect of UV light. When the active ingredients of sunscreen absorb UV light, a chemical change triggers the generation of oxygen-carrying molecules known as reactive oxygen species (ROS). If a sunscreen’s agents penetrate the skin, this chemical change could cause cellular damage, and potentially facilitate skin cancer.

“Commercial chemical sunblock is protective against the direct hazards of ultraviolet damage of DNA, but might not be against the indirect ones,” said co-author Michael Girardi, a professor of dermatology at Yale Medical School. “In fact, the indirect damage was worse when we used the commercial sunblock.”

Girardi, who specializes in skin cancer development and progression, said little research has been done on the ultimate effects of sunblock usage and the generation of ROS, “but obviously, there’s concern there.”

Previous studies have found traces of commercial sunscreen chemicals in users’ bloodstreams, urine, and breast milk. There is evidence that these chemicals cause disruptions with the endocrine system, such as blocking sex hormone receptors.

To test penetration levels, the researchers applied strips of adhesive tape to skin previously treated with sunscreen. The tape was then removed rapidly, along with a thin layer of skin. Repeating this procedure allowed the researchers to remove the majority of the outer skin layer, and measure how deep the chemicals had penetrated into the skin. Traces of the sunscreen chemical administered in a conventional way were found to have soaked deep within the skin. The Yale team’s sunblock came off entirely with the initial tape strips.

Tests also showed that a substantial amount of the Yale team’s sunscreen remained on the skin’s surface for days, even after exposure to water. When wiped repeatedly with a towel, the new sunblock was entirely removed. [emphasis mine]

To make the sunblock, the researchers developed a nanoparticle with a surface coating rich in aldehyde groups, which stick tenaciously to the outer skin layer. The nanoparticle’s hydrophilic layer essentially locks in the active ingredient, a hydrophobic chemical called padimate O.

Some sunscreen solutions that use larger particles of inorganic compounds, such as titanium dioxide or zinc oxide, also don’t penetrate the skin. For aesthetic reasons, though, these opaque sunscreen products aren’t very popular. By using a nanoparticle to encase padimate O, an organic chemical used in many commercial sunscreens, the Yale team’s sunblock is both transparent and stays out of the skin cells and bloodstream.

This seems a little confusing to me and I think clarification may be helpful. My understanding is that the metallic nanoparticles (nano titanium dioxide and nano zinc oxide) engineered for use in commercial sunscreens are also (in addition to the macroscale titanium dioxide and zinc oxide referred to in the Yale news release) too large to pass through the skin. At least that was the understanding in 2010 and I haven’t stumbled across any information that is contradictory. Here’s an excerpt from a July 20, 2010 posting where I featured portions of a debate between Georgia Miller (at that time representing Friends of the Earth) and Dr. Andrew Maynard (at that time director of the University of Michigan Risk Science Center and a longtime participant in the nanotechnology risk discussions),

Three of the scientists whose work was cited by FoE as proof that nanosunscreens are dangerous either posted directly or asked Andrew to post comments which clarified the situation with exquisite care,

Despite FoE’s implications that nanoparticles in sunscreens might cause cancer because they are photoactive, Peter Dobson points out that there are nanomaterials used in sunscreens that are designed not to be photoactive. Brian Gulson, who’s work on zinc skin penetration was cited by FoE, points out that his studies only show conclusively that zinc atoms or ions can pass through the skin, not that nanoparticles can pass through. He also notes that the amount of zinc penetration from zinc-based sunscreens is very much lower than the level of zinc people have in their body in the first place. Tilman Butz, who led one of the largest projects on nanoparticle penetration through skin to date, points out that – based on current understanding – the nanoparticles used in sunscreens are too large to penetrate through the skin.

However, there may be other ingredients which do pass through into the bloodstream and are concerning.

One other thing I’d like to note. Not being able to remove the sunscreen easily ( “When wiped repeatedly with a towel, the new sunblock was entirely removed.”) may prove to be a problem as we need Vitamin D, which is for the most part obtainable by sun exposure.

In any event, here’s a link to and a citation for the paper,

A sunblock based on bioadhesive nanoparticles by Yang Deng, Asiri Ediriwickrema, Fan Yang, Julia Lewis, Michael Girardi, & W. Mark Saltzman. Nature Materials (2015) doi:10.1038/nmat4422 Published online 28 September 2015

This paper is behind a paywall.

*’teh’ changed to ‘the’ on June 6, 2016.

Sunscreen based on algae, reef fish mucus, and chitosan

The proposed sunscreen is all natural and would seem to avoid some of the environmental problems associated with other sunscreens (e.g., washing off into the ocean and polluting it). From a July 29, 2015 American Chemical Society (ACS) news release (also on EurekAlert), Note: Links have been removed,

For consumers searching for just the right sunblock this summer, the options can be overwhelming. But scientists are now turning to the natural sunscreen of algae — which is also found in fish slime — to make a novel kind of shield against the sun’s rays that could protect not only people, but also textiles and outdoor materials. …

Existing sunblock lotions typically work by either absorbing ultraviolet rays or physically blocking them. A variety of synthetic and natural compounds can accomplish this. But most commercial options have limited efficiency, pose risks to the environment and human health or are not stable. To address these shortcomings, Vincent Bulone, Susana C. M. Fernandes and colleagues looked to nature for inspiration.

The researchers used algae’s natural sunscreen molecules, which can also be found in reef fish mucus and microorganisms, and combined them with chitosan, a biopolymer from crustacean shells. Testing showed their materials were biocompatible, stood up well in heat and light, and absorbed both ultraviolet A and ultraviolet B radiation with high efficiency.

The authors acknowledge funding from the European Commission Marie Curie Intra-European Fellowship, the KTH Advanced Carbohydrate Materials Consortium (CarboMat), the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS) and the Basque Government Department of Education.

Here’s a link to and a citation for the paper,

Exploiting Mycosporines as Natural Molecular Sunscreens for the Fabrication of UV-Absorbing Green Material by Susana C. M. Fernandes, Ana Alonso-Varona, Teodoro Palomares, Verónica Zubillaga, Jalel Labidi, and Vincent Bulone.
ACS Appl. Mater. Interfaces, Article ASAP DOI: 10.1021/acsami.5b04064 Publication Date (Web): July 13, 2015
Copyright © 2015 American Chemical Society

This paper is behind a paywall.