Nanoparticles and the skin--applications and limitations.

In recent years, nanotechnology and nanoengineering have stimulated much research in the field of drug delivery. This review examines the different types of non-deformable nanoparticles (NP) which have been developed for pharmaceutical applications. Metal, metallic oxide, polymeric, starch, quantum dot, fullerene and carbon nanotube NP are discussed. Only those studies which have focused on particle interaction with human and porcine skin models in vitro and in vivo are considered. Particular emphasis is given to the disposition and transfer of NP in the skin. As the methodology and experimental design of published studies should have an impact on the results obtained, these are also critically examined.