Abstract

The trans-cutaneous pathway for drug delivery is of particular interest since it allows a simple and non-invasive administration of pharmaceutically relevant compounds. As the skin is an effective barrier for many of these compounds, various strategies have been developed to enable and control the trans-cutaneous transport. Here we discuss, how multiphoton microscopy and spectral imaging can be valuable tools for the analysis of the penetration pathways of topically applied drugs. A time dependent study of the cutaneous penetration of a fluorescent drag model released from a nano-particular carrier is presented. The localization of single nano-particles in human skin (ex vivo) and the discrimination of different fluorescent compounds, as the drag model, the particle's label and the cutaneous endo-fluorescence by spectral imaging and selective excitation is shown. Multiphoton imaging techniques were found to be excellent methods for the non-invasive evaluation of cutaneous drag delivery strategies and analysis of dermal penetration pathways down to the sub-cellular level.

© 2007 SPIE