Nanoparticles Join War on Wrinkles

Jan. 25, 2007 — The latest development in cosmetic nanotechnology could help stop wrinkles before they start.

When added to thin polymer films used in industry as protective coatings or transistors, tiny nanoparticles help prevent the materials from buckling in a way that can reduce performance. But researchers think the particles may have cosmetic applications as well.

"In the industries of biomechanics, artificial skins, plastic surgery, and cosmetics, controlling and ultimately preventing such unavoidable wrinkling phenomena is of great interest to many people," said Ilsoon Lee of Michigan State University, who collaborated on the research with Ph.D. student Troy Hendricks.

Lee thinks that the same technique he developed for polymer films could be applied to human skin.

Wrinkles, in both polymer films and skin, occur for similar reasons. External forces, such as those from heat (in the case of polymers) or muscles (in the case of skin) compress the pliable substance, causing it to buckle.

In thin film transistors, buckling is bad because it makes the electric current less efficient. But as computer parts get smaller, and transistors get thinner, the chance for wrinkling increases exponentially.

When buckling occurs in thin films — used as protective surfaces, antireflective coatings and lubricating layers — the result can range from small cracks to catastrophic failure.

>Lee and Hendricks suspended nanoparticles in the film like grapes in a Jello mold. When external forces squeezed the film, each particle deflected a tiny bit of local tension. Working together, the particles reduced the overall strain on the film, preventing wrinkles.

One way to reap cosmetic potential out of the same technique might be to inject the particles into the skin or put them in a topical cream.

Another solution could be done during a cosmetic procedure, such as a facelift or eyelift. In those cases, a film with the nanoparticles could be implanted in the skin or transferred to the skin's surface like a transparent toy tattoo. The film could stay there temporarily or permanently to ward off muscle tensions that cause wrinkles.

But the skin is not a smooth surface to begin with, said Vladimir Tsukruk, professor of materials science and engineering at Georgia Institute of Technology in Atlanta. It has a complex topography of pores, hairs and its own protection oily layer.

"It is not obvious that such a complex 'sandwich' will behave accordingly," he said.

Currently, Lee's team is applying the nanoparticles to various cells and proteins to see if there are any toxic reactions.

But even if the body rejects the silica nanoparticles the team is currently using, Lee thinks other FDA-approved particles could be substituted.