Scientists at MIT, Massachusetts General Hospital, Living Proof, and Olivo Labs have developed
a new material that can temporarily protect and tighten skin, and smooth wrinkles. With
further development, it could also be used to deliver drugs to help treat skin conditions
such as eczema and other types of dermatitis. 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. This type of “second skin” could also be adapted to provide long-lasting
ultraviolet protection. 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. As skin ages, it becomes less firm and less
elastic — problems that can be made worsen by sun exposure. This impairs skin’s ability
to protect against extreme temperatures, toxins, microorganisms, radiation, and injury. 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.
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.
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. 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 where “eye bags” often form as skin ages. These eye
bags are caused by protrusion of the fat pad underlying the skin of the lower lid. 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 novel XPL suffered much less water
loss than skin treated with a high-end commercial moisturizer. Skin coated with petrolatum / petroleum
jelly 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.