Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Artificial skin tests for stopping sun damage

11.08.2016

Sun rays damage unprotected skin. Substances in medications or lotions applied to the skin can be chemically modified by sun rays to have a toxic effect on the body. An accredited in-vitro test method at Fraunhofer IGB in Stuttgart measures the phototoxic potential of substances or cosmetics. The skin model was advanced with the addition of pigmentation that enables the testing of self-tanning agents.

Sunbathing without sunscreen can be dangerous. Sun rays do not only damage the skin. Some substances in drugs, cosmetics and medicinal herbs can be toxic to the skin when exposed to ultraviolet light.


Fraunhofer researchers irradiate their skin model in the UV irradiation unit with defined non-toxic UV dosages.

Fraunhofer IGB

Experts call the phenomenon phototoxicity. It occurs when a substance absorbs light energy and is thereby chemically modified. Only the modified substance is toxic to the skin, which can cause redness, swelling or inflammation - similar to a sunburn.

Companies can examine the phototoxicity of a substance with an in-vitro test methods developed at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB. The test procedure is ISO certified and meets the required norms and standards.

Phototoxic substances - Feels like sunburn

The test procedure is performed on an in vitro skin model built at Fraunhofer IGB from human skin cells in special culture dishes. A fully developed epidermis model is used to study phototoxic effects. “We culture typical skin cell of the epidermis, such as human keratinocytes, in our dishes to form an artificial epidermis with all of its natural layers”, explained Sibylle Thude, the biologist who led the investigation into the accreditation.

“The typical horny layer of the skin developes on the top of the model, which acts as an important barrier against dehydration and environmental influences.”

Substances are tested on a mature epidermis model by applying them to the surface of the epidermis and exposing the model to defined, but non-toxic, doses of UV radiation. The skin cells that create the model are then tested to verify if they are still alive or have been damaged.

“We first look at the skin models under the microscope“, explained Thude. Each sample is then examined with a spectrometer to precisely quantify the extent of cell damage. “If the vitality of the skin model is damaged by more than 30 percent when compared to a non-irradiated model, we classify the test substance as a phototoxic”, said Thude. The test method is validated for aqueous solutions and oils, to the OECD Guideline 432 and the INVITTOX protocol 121, and assessed by the German Accreditation Body (DAkkS).

Self-tanning with sunscreen

Another skin model helps discover substances that stimulate melanin production of the skin. Self-tanners are of great interest, since they not only tone the skin, but also help build the body's own UV protection. To identify those substances, researchers add melanocytes to the epidermis model. Melanocytes play an important protective role in human skin: In sunlight they form the pigment melanin which adsorbs harmful UV radiation and thus prevents sunburn.

“We irradiate the pigmented skin model with UV light to directly measure increased melanin production,“ explained Thude. They also measure melanogenic substances such as L-dihydroxy-phenylalanine which is a precursor of melanin. Skin lightening substances, such as creams that hide aging spots, can also be tested on the pigmented skin model.

Since 2013, cosmetics whose ingredients have been tested on animals can no longer be sold within the EU. The Fraunhofer IGB develops alternatives based on human cells to verify the biocompatibility of substances.

Dr. Claudia Vorbeck | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB
Further information:
http://www.igb.fraunhofer.de/

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>