Phototoxic or Photoprotective?-Advances and Limitations of Titanium (IV) Oxide in Dermal Formulations-A Review

The widespread role of titanium (IV) oxide (TiO2) in many industries makes this substance of broad scientific interest. TiO2 can act as both a photoprotector and photocatalyst, and the potential for its role in both applications increases when present in nanometer-sized crystals. Its sunlight-scattering properties are used extensively in sunscreens. Furthermore, attempts have been made to incorporate TiO2 into dermal formulations of photolabile drugs. However, the propensity to generate reactive oxygen species (ROS) rendering this material potentially cytotoxic limits its role. Therefore, modifications of TiO2 nanoparticles (e.g., its polymorphic form, size, shape, and surface modifications) are used in an effort to reduce its photocatalytic effects. This review provides an overview of the potential risks arising from and opportunities presented by the use of TiO2 in skin care formulations.

Automated summary

The widespread use of titanium (IV) oxide (TiO2) in various industries has attracted significant scientific attention. TiO2 can serve as both a photoprotector and a photocatalyst, with enhanced potential in nanometer-sized crystals. Its ability to scatter sunlight is extensively utilized in sunscreens, and efforts have been made to incorporate TiO2 into dermal formulations of photosensitive drugs. However, its tendency to generate reactive oxygen species (ROS), which can be cytotoxic, hinders its full potential. Therefore, modifications of TiO2 nanoparticles such as polymorphic form, size, shape, and surface modifications are explored to minimize its photocatalytic effects. This review provides an overview of the potential risks and opportunities associated with the use of TiO2 in skin care formulations.