Nanocrystalline titanium dioxide and magnesium oxide in vitro dermal absorption in human skin

Abstract

The dermal absorption potential of a nanocrystalline magnesium oxide (MgO) and titanium dioxide (TiO₂) mixture in dermatomed human skin was assessed in vitro using Bronaugh-type flow-through diffusion cells. Nanocrystalline material was applied to the skin surface at a dose rate of  50 mg/cm² as a dry powder, as a water suspension, and as a water/surfactant (sodium lauryl sulfate) suspension, for 8 hours. Dermal absorption of nanocrystalline MgO and TiO₂ through human skin with intact, functional stratum corneum was not detectable under the conditions of this experiment.

Keywords::

• Dermal absorption
• metal oxides
• nanocrystalline
• titanium dioxide
• magnesium oxide

Acknowledgments

This work was sponsored by NanoScale Corporation, Inc., and the US Army REDCOM (Contract Number W911SR-07-C-0062), and their support is acknowledged with gratitude. The views and conclusions contained in this report are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the United States Army, or the U.S. Government. No official endorsement should be inferred. We thank Dr. Daniel L. Boyle (Division of Biology, Kansas State University) for preparing transmission electron microscopy images.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.