Imaging of Zinc Oxide Nanoparticle Penetration in Human Skin In Vitro and In Vivo
January 2008
in “
Journal of biomedical optics
”
TLDR Zinc oxide nanoparticles in sunscreen do not penetrate deep into the skin.
The study investigated the penetration of zinc oxide nanoparticles (ZnO-nano) in human skin using various imaging techniques and found that ZnO-nano remained in the stratum corneum and did not penetrate deeper skin layers. This was confirmed through both in vitro and in vivo experiments involving human subjects of different ethnic backgrounds. The findings suggested that ZnO-nano used in sunscreens is unlikely to pose safety concerns due to its lack of subdermal penetration.