Microneedle, An Innovative Approach to Transdermal Drug Delivery

Transdermal drug delivery system (TDDS) is a newer technique which offer delivery of drug via skin at controlled rate and prolong duration. Microneedles (MNs) are the recent advancement in the TDDS which can deliver high molecular weight drug by penetrating into the skin. MNs become popular due to avoidance of first pass metabolism, good patient compliance, rapid, easy and painless administration. Solid, coated, hollow, dissolvable and hydrogel-forming are the types of MNs having their own merits and demerits. MNs are generally prepared from silicon and used to deliver drugs, hormones, peptides, protein, vitamin, plasmid DNA, and vaccine in a safe and effective way. The working principle and the four different strategies for TDDS using a MNs array are poke and patch, coat and poke, poke and released, poke and flow technique. At present number of preclinical and clinical research is going on for the enhancement of permeability, stability and delivery of drug using MNs. This review focused on the types, manufacturing, current status and method of evaluation of MN in pharmaceutical research.