Advances and controversies in studying sunscreen delivery and toxicity

Sunscreens contain substances that either absorb or reflect the UV rays and prevent most of it from penetrating the skin and damaging skin cells. The skin cancer rate, however, is rising despite many studies showing sunscreens protect skin cells from UV damage. A possible explanation is poor sunscreen application, penetration problems or inadvertent removal reducing efficacy. There have been intensive studies to investigate the depth of delivery of sunscreens and off-target effects in skin cells, but little is known about sunscreen application efficiency and removal. In this talk, the current models that have been developed as a surrogate for human skin will be discussed and novel approaches, we have taken to examine sunscreen penetration and off-target effects. We present a minimally invasive approach using advanced imaging technologies and microbiopsy sampling that removes significant hurdles when studying cosmeceuticals. Multiphoton microscopy of treated volunteer skin will be discussed as a means to evaluate sunscreen nanoparticle penetration into viable epidermis in intact and barrier disrupted skin. We see these data as support for the development of standardized microbiopsy based nanotoxicology testing for topical engineered materials.

In 2004, Dr. Prow earned his Ph.D. from the University of Texas in the field of Nanomedicine. He then completed his T32 funded post-doc at the Wilmer Eye Institute at The Johns Hopkins Hospital and was faculty there until he relocated to the University of Queensland in Brisbane, Australia in 2007. In 2011 Dr. Prow became the Deputy Director of the Dermatology Research Centre. In 2015, Dr. Prow was promoted to Associate Professor within the University of Queensland’s School of Medicine and began his NHMRC CDF Level II Fellowship the following year. He now focuses on translational outcomes from his NHMRC funded micromedical device development team as a Research Professor in the Biomaterials Engineering and Nanomedicine Strand within the Future Industries Institute at The University of South Australia.