Compounding with Microneedle Arrays, Part 2: Preparation and Administration Methods

As discussed in the first article in this series, microneedle arrays are minimally invasive devices that can be used to bypass the stratum corneum barrier and thus achieve transdermal drug delivery. Microneedles in various geometries and materials (silicon, metal, polymer) have been produced using microfabrication techniques. Microneedle arrays appear similar to transdermal patches, ranging upwards in size from 1 cm2 to larger sizes depending upon the drug, etc. The concept of microneedle structures to penetrate painlessly the outermost layer of the skin, the stratus corneum, was first introduced in the 1970s. This article, which represents part 2 of this series of articles, discusses the current state of microneedle array development and the compounding opportunities, using the pretreatment approach.