Imagine skin that, when injured, can regrow and heal itself in rapid fashion. It sounds like something out of a comic book or science fiction movie, but this idea is coming to life thanks to the work of a group of chemists and engineers at Stanford University. These scientists have designed a plastic skin that is capable of feeling and healing itself.
There have been many attempts in recent years by scientists to create such a substance, but so far all have failed due to various inconsistencies. Some could only heal once and then would fall apart. Others would only work at certain temperatures, usually the extremes of hot and cold ranges. This new skin, composed of polymers, is sensitive to touch, temperature and pressure, and has the ability to heal itself if cut. The team of scientists, led by chemical engineer Zhenan Bao, combined the two elements of electrical conductivity and self-healing to design a successful plastic skin.
How does this plastic skin heal? It all has to do with the chemical bonds. At a microscopic level, the skin is made up of chains of molecules that are connected by hydrogen bonds. This forms weak attractions between the positively charged and negatively charged areas of atoms (that is, between atoms that are polar in nature). The bonds break easily but are quickly able to reconnect and reorganize themselves. This allows the material to, if damaged, return to its former healed state.
The researchers also added small particles of nickel to the plastic skin with the intention of increasing its strength. The nickel also helped to make the polymer conductive, with the rough edges of the nickel particles helping to concentrate electrical field on the particles. This ability of the plastic skin to generate an electrical field is essential to the technology portion of this project. In order for the skin to feel pressure, temperature and operate overall, electricity needs to be able to be transferred from some mechanism to the new plastic skin. This had to be on par with what humans feel as objects come in contact with our skin.
The researchers have statistical evidence to prove the effectiveness of their product. To test the healing power of the material, the scientists repeatedly make slices in it with a scalpel. After breaking the bonds, they would gently push the separated pieces together and within seconds the material regained 75 percent of its original strength. In 30 minutes it was back to full strength, as it was before it was sliced.
This presents an amazing aspect of this technology in that its healing rate is much faster than even human skin. They continually cut the same piece of material and even after hundreds of slices, the plastic skin healed back to its original strength.
There is no doubt that this technology is an astonishing accomplishment in the science, engineering and health industries. This healing plastic skin could be incredibly helpful in the health field in the form of prosthetic limbs. The sensitivity of the skin could provide a way for people with prosthetic limbs to touch and feel with their replacement limbs. With more advanced and versatile prosthetic limbs being built, the addition of the feeling skin could provide an incredibly realistic replacement arm. This would allow people with prosthetic limbs to be more active and would help them perform much more advanced tasks that they were not able to do before. Also, this sort of regenerating skin could coat prosthetic limbs to give a more natural feel and look to the part. The material is very flexible and would be able to bend around joints in the prosthetic equipment and could add a more realistic feel to it.
Additionally, the plastic skin could be extremely helpful to people recovering from severe burns or wounds. The plastic could cover burns to provide a source of protection for the burnt area and would be able to take over as the arm’s skin as the real skin regenerates underneath. The plastic could also be used similarly to cover wounds as they heal, both protecting the area from infection and irritation. Even if the polymer protective skin splits or breaks in some situation, it regenerates in a matter of seconds.
This new plastic skin is a major breakthrough in science that seems quite futuristic and fictional. However, it’s a great reminder that great things are constantly being done by scientists in order to improve people’s lives.
Luke Dery is a Collegian columnist. He can be reached at [email protected].