Drug delivery across skin has been limited due to barrier properties of the skin, especially those of the stratum corneum. Use of the laser radiation has been suggested for the controlled removal of the stratum corneum and a great enhancement of transdermal drug delivery in laser-stripped skin has been reported. The mechanisms of lasers to enhance drug delivery via skin are both the stratum corneum ablation and photomechanical waves to cause ultrastructural alteration. According to the report, the popularity of cosmetic laser treatments in Taiwan is increasing. More and more people opting for laser resurfacing to minimize wrinkles and facial spots. In most cases, topically applied antibiotics and sunscreen will be recombined by physician to avoid inflammation and hyperpigmentation of the skin after laser treatment. However, laser-treatment enhanced permeation may also influence the absorption, distribution and local concentration of topically applied antibiotics and metal particles in sunscreen. For example, titanium dioxide (TiO2) and zinc oxide (ZnO) are tiny metal particles that reflect and scatter UV light. They normally won't be able to penetrate the barrier of the skin. Unfortunately, it might be changed if stratum corneum was partially removed or ultrastructural alteration of the skin. The purpose of this study is to evaluate the influence of the fraxel laser on transdermal delivery of antibiotics, nano TiO2 and ZnO particles in vitro and in vivo. We will investigate the penetration and the distribution of antibiotics, nano TiO2 and ZnO particles in the nude mice skin treated with laser. The fluorescence-labeled nanoparticles were prepared to indicate the transdermal transport process of the nanoparticles. The cytotoxic effect and the toxic mechanism of nano TiO2 and ZnO particles will be evaluated. This study will provide useful information for topical drug administration and potential concern for nanoparticles after laser treatment.
|Effective start/end date||8/1/11 → 7/31/12|