Transdermal transport microneedles

Up to now, the development of microneedles has focused on microfabrication techniques for Si and other biocompatible materials. Currently, there are several commercially available microneedle products, such as MTS (Microstructured Transdermal System) by 3 M, Macroflux by ALZA, and Micro-Trans by Bio Valve Technologies, and most of them are designed to increase skin permeability and adopt passive delivery methods (i.e., capillary force). As the feasibility of microneedles is well established, the next step is to understand the characteristics of fluid transport by microneedles,... 

Gardeniers HJGE et al (2003) Silicon micromachined hollow microneedles for transdermal liquid transport. J Microelectro-998 mechan Syst 12(6)... 

Skin microporation is investigated for transdermal delivery of water-soluble small drugs and macromolecules such as proteins. It involves the creation of micron dimension transport pathways in the skin using a minimally invasive technique, such as microneedles, thermal microporation, or radiofrequency ablation. An applicator can be used to apply the microneedles on the skin to create the micropores followed by patch application. Alternatively, the drug can be coated directly on the microneedles. The latter approach has been used for vaccine delivery since the amount of protein antigen needed to generate immune response is very small and the dose can be accommodated by coating the microneedles [110]. 

---