With the launch of few products in the market, transdermal drug delivery through microneedles (MNs) has evidenced a major leap. Interest in MNs is growing exponentially as it overcomes the limitations accompanying other delivery routes. Among the various types of MNs, polymeric microneedles (PMNs) seem to be more propitious because of the associated favourable innate properties. Nevertheless, struggle in loading capacity, unmanageable rate of drug release, and monotonic curative approach hampers the further development of PMNs. Recent emerging research has drawn inspiration from nanocarriers and in conjunction with PMNs have opened up new perspectives for the treatment of various diseases. In this review, we focus on recent progresses in the field of transdermal drug delivery using nano carriers in conjunction with PMNs for various therapeutic and diagnostic activities. Additionally, we describe the various factors impacting drug delivery, and challenges involved in sterilization and stability aspects associated with nanocarrier loaded PMNs, highlighting future research perspectives alongside.
Polymeric microneedles for transdermal delivery of nanoparticles: Frontiers of formulation, sterility and stability aspects