A Hydrogel/Carbon-Nanotube Needle-Free Device for Electrostimulated Skin Drug Delivery

The permeability of skin allows passive diffusion across the epidermis to reach blood vessels but this is possible only for small molecules such as nicotine. In order to achieve transdermal delivery of large molecules such as insulin or plasmid DNA, permeability of the skin and mainly the permeability of stratum corneum has to be increased. Moreover, alternative routes that avoid the use of needles will improve the quality of life of patients. A method named “electropermeabilization” has been shown to increase skin permeability. Here, we report the fabrication of an innovative hydrogel, made of nanocomposite material. This nanocomposite device aims at permeabilizing the skin and delivering drug molecules at the same time. It includes a biocompatible polymer matrix (hydrogel) and double walled-carbon-nanotubes (DWCNTs) in order to bring electrical conductivity and improve mechanical properties. Carbon nanotubes and especially DWCNTs are ideal candidates, combining high electrical conductivity with a very high specific surface area together with a good biocompatibility when included into a material. The preparation and characterization of the nanocomposite hydrogel as well as first results of electro stimulated transdermal delivery using an ex vivo mouse skin model are presented