MIT researchers have created a kind of second skin, a silicone-based polymer that could be applied on the existing skin as a thin, imperceptible coating. The material 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. This type of “second skin” could also be adapted to provide long-lasting ultraviolet protection, the researchers say.
“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,” says Daniel Anderson, 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).
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 percent (natural skin can be elongated about 180 percent). In laboratory tests, the novel 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,” says 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, nonirritating, and able to conform to the movement of the skin and return to its original shape.”
The XPL is currently delivered in a two-step process. First, polysiloxane components are applied to the skin, followed by a platinum catalyst that induces the polymer to form a strong cross-linked film that remains on the skin for up to 24 hours. This catalyst has to be added after the polymer is applied because after this step the material becomes too stiff to spread. Both layers are applied as creams or ointments, and once spread onto the skin, XPL becomes essentially invisible.
John Varley, in his amazing (still amazing!) 1983 novel Millennium, described skinsuits that the people of the future were forced to wear to conceal their deformities and diseases when time traveling back to the present.
Nobody but me and my doctor and Sherman know which of my organs and limbs are my own, and I'm happy to keep it that way. I must care, or I wouldn't live in this lying skinsuit pretending to be a film star from the year 2034. That's right; the me everybody knows is patterned, down to the last birthmark, on a glamor queen we snatched from a terrorist explosion.
(Read more about skinsuits)