Exploring new frontiers in drug delivery with minimally invasive microneedles: fabrication techniques, biomedical applications, and regulatory aspects

Transdermal drug delivery is limited by the stratum corneum, inhibiting the therapeutic potential of the permeants. Microneedles (MNs) have opened new frontiers in transdermal drug delivery systems. These micro-sized needles offer painless and accentuated delivery of drugs even with high molecular weights.The review embodies drug delivery strategies with MNs with a description of MN types and fabrication techniques using various materials. The application of MN is not limited to drug delivery, but it also encompasses in vaccine delivery, diagnosis, phlebotomy, and even in the cosmetic industry. The review also tabulates MN-based marketed formulations. In a nutshell, we aim to present a panoramic view of MNs, including the design, applications, and regulatory aspects of MN.With the availability of numerous materials at the disposal of pharmaceutical scientists; the MN-based drug delivery technology has offered significant interventions toward the management of chronic maladies, including cardiovascular disorders, diabetes, asthma, mental depression, etc. As happens with any new technology, there are concerns with MN also such as biocompatibility issues with the material used for the fabrication. Nevertheless, the pharmaceutical industry must strive for preparing harmless, efficient, and cost-effective MN-based delivery systems for wider acceptance and patient compliance.