Scientists have developed a “second skin” that can temporarily protect and tighten skin and smooth wrinkles. With further development, the material could also be used to deliver therapies to help treat skin conditions such as eczema and other types of dermatitis, according to a paper published in an online issue of Nature Materials (May 9, 2016).
The material, a silicone-based polymer that could be applied on the skin as a thin, imperceptible coating, mimics the mechanical and elastic properties of healthy, youthful skin. In tests with human subjects, the researchers found that the material was able to reshape “eye bags” under the lower eyelids and also enhance skin hydration. It could also be adapted to provide long-lasting ultraviolet protection, said the researchers from the Massachusetts Institute of Technology (MIT) in Cambridge, Mass., and Massachusetts General Hospital (MG) in Boston.
“It’s an invisible layer that can provide a barrier, provide cosmetic improvement, and potentially deliver a drug locally to the area that’s being treated. Those three things together could really make it ideal for use in humans,” said Daniel Anderson, PhD, one of the study’s authors and an associate professor in MIT’s Department of Chemical Engineering and a member of MIT’s Koch Institute for Integrative Cancer Research and Institute for Medical Engineering and Science (IMES), in a press release.
Mimicking skin
About 10 years ago, the research team set out to develop a protective coating that could restore the properties of healthy skin, for both medical and cosmetic applications.
The researchers created a library of more than 100 possible polymers, all of which contained a chemical structure known as siloxane—a chain of alternating atoms of silicon and oxygen. These polymers can be assembled into a network arrangement known as a cross-linked polymer layer (XPL). The researchers then tested the materials in search of one that would best mimic the appearance, strength, and elasticity of healthy skin.
Photo: Melanie Gonick/MIT
The best-performing material has elastic properties very similar to those of skin. In laboratory tests, it easily returned to its original state after being stretched more than 250%. In laboratory tests, the XPL’s elasticity was much better than that of two other types of wound dressings now used on skin—silicone gel sheets and polyurethane films.
“Creating a material that behaves like skin is very difficult,” said Dr. Barbara Gilchrest, a dermatologist at MGH and an author of the paper. “Many people have tried to do this, and the materials that have been available up until this have not had the properties of being flexible, comfortable, non-irritating, and able to conform to the movement of the skin and return to its original shape.”
High performance
The researchers performed several studies in humans to test the material’s safety and effectiveness. In one study, the XPL was applied to the under-eye area. When the material was applied, it applied a steady compressive force that tightened the skin, an effect that lasted for about 24 hours.
In another study, the XPL was applied to forearm skin to test its elasticity. When the XPL-treated skin was distended with a suction cup, it returned to its original position faster than untreated skin.
The researchers also tested the material’s ability to prevent water loss from dry skin. Two hours after application, skin treated with the XPL experienced much less water loss than skin treated with a high-end commercial moisturizer. Skin coated with petrolatum was as effective as XPL in tests done two hours after treatment, but after 24 hours, skin treated with XPL had retained much more water. None of the study participants reported any irritation from wearing XPL.
An MIT video (above) demonstrates how “second skin” works.
Photo: Olivo Labs