Researchers modified titanium dioxide nanoparticles (used in sunscreen) by coating them with a protein that reduced how much they penetrate skin by 89-91%. The coated particles still protected against UV damage and DNA damage just as well as regular titanium dioxide, but stayed on the skin surface instead of being absorbed into cells.

Scientists tested two types of titanium dioxide nanoparticles—regular ones and ones coated with a protein called BSA—on human skin cells and in lab models of skin penetration. They measured how much each type got absorbed, whether they caused damage, and how well they blocked UV rays.

Funding not disclosed in abstract