Novel (Trans)dermal Drug Delivery Strategies: Micro- and Nano-scale Assessments

Abstract

This work represents an inventive attempt to apply recent advances in nanotechnology to identify and characterise novel polymer systems for drug delivery through the skin. Atomic force microscopy (AFM) measurements of the nanoscale mechanical properties of topical, drug-containing polymeric films enabled the author to identify optimal compositions, in terms of flexibility and substantivity, for application to the skin. To elucidate the enhanced drug release from polyacrylate films incorporating medium chain triglycerides, the author combined AFM studies with the complementary technique of Raman micro-spectroscopy. This experimental strategy revealed that the significant increase in the drug released from these films is the result of a nanoscale two-phase structure. Finally, in experiments examining the microporation of skin using femtosecond laser ablation, the author demonstrated that the threshold at which the skin's barrier function is undermined can be dramatically reduced by the pre-application of ink. The approach allows thermal damage at the pore edge to be minimised, suggesting a very real potential for substantially increasing drug delivery in a minimally invasive fashion.