Microneedle-Based Transdermal Drug Delivery Systems: A Comprehensive Review on Materials, Fabrication Techniques, and Types

Abstract

Microneedle (MN)-based transdermal drug delivery systems represent a cutting-edge approach to administer therapeutic agents through the skin with enhanced efficacy and patient compliance. Traditional transdermal delivery is limited by the stratum corneum barrier, restricting the passage of most drugs. MNs, typically ranging from 25 to 2000 µm in length, create transient microchannels in the skin, allowing drugs to bypass this barrier without causing significant pain or bleeding. Various types of MNs, including solid, hollow, coated, dissolvable, and hydrogel-forming MNs, have been developed to accommodate different drug formulations and delivery mechanisms. Fabrication techniques such as micromolding, lithography, laser ablation, enable precise control over MN geometry, density, and mechanical strength, which are critical factors for effective skin penetration. And controlled drug release. Materials used range from metals and silicon to biocompatible polymers, ensuring safety and structural integrity. MN-based systems have shown significant potential for delivering vaccines, insulin, hormones, and small molecule drugs, offering advantages such as reduced dosing frequency, improved pharmacokinetic profiles, and avoidance of first-pass metabolism. Despite these advancements, challenges including large-scale manufacturing, stability of biologics, and patient-specific skin. Variability remain. Future directions focus on integrating MNs with nanotechnology, biosensors, and wearable devices to enable real-time monitoring, controlled release, and personalized therapy. Overall, MN-based transdermal systems hold promise as a minimally invasive, versatile, and patient-friendly platform that could revolutionize drug administration across various therapeutic areas.