Non-Penetrating Sunscreen

While sunscreens may be effective at protecting skin from damaging UV rays, they aren’t without risks and concerns. Research has suggested that when the active ingredients in sunscreen absorb UV light, it triggers a chemical change that generates molecules known as reactive oxygen species (ROS). Furthermore, if the agent penetrates the skin, it could cause the very type of cellular damage that leads to skin cancer. Other non-penetrating solutions are available that use large molecule, inorganic compounds like titanium oxide, but they are opaque, making them unpopular for aesthetic reasons.

But a new type of sunscreen has been developed that stays on the skin without being absorbed into it. The commonly used UV-absorbing chemical – padimate 0 – is coated with a biodegradable nanopolymer. The nanoparticles are large enough that they don’t penetrate the skin surface. They’re also sticky enough that they’ll stay out of hair follicles. The result is a transparent sunscreen that isn’t absorbed, won’t wash off with water and can only be removed by wiping with a towel. In addition, because it stays on the skin surface, the new sunscreen requires a smaller amount of active ingredient to be effective.

A small-scale study on human subjects will be conducted to establish the SPF. It is hoped that minimizing the risk of exposure to potentially harmful chemicals will encourage more people to use sunscreen in the future.