Microneedles: bench to bedside.

Microneedles are tiny micron-sized structures, made of a variety of materials, used to minimally disrupt the outermost layer of the skin for enhancing the delivery of therapeutic molecules across the skin. They are sufficiently long enough just to breach the stratum corneum barrier but too short to reach the nerve endings that perceive pain. Treating the skin using microneedles results in the creation of aqueous microchannels that promote delivery of molecules practically of any size. Small molecules, proteins, vaccines and diagnostic agents can be delivered using microneedles. This technology that has started with microstructures made of metal and silicon has now undergone significant advances in the last decade and currently there are microneedle products in the market.