Chapter 6 - Hydrogel-forming microarray patches for drug delivery and diagnostic applications: Advances in the Manufacture, Characterization, and Application of Hydrogels to Address Current Global Healthcare Challenges

Hydrogel-forming microarray patches (HF-MAPs) are innovative microneedle-based devices capable of painlessly penetrating the skin's outer layer, providing a platform for controlled and high-dose transdermal drug delivery. These MAPs, made from crosslinked polymers, feature a unique design that enables the absorption of interstitial fluid upon skin insertion, creating conduits between the microcirculation and drug reservoir situated on top of the MAP. The versatility of HF-MAPs extends to various drug delivery applications, including low molecular weight (MW) drugs and high molecular weight biotherapeutics. Fabricated using synthetic or natural polymers, HF-MAPs have shown promise in delivering a wide range of therapeutic agents, addressing challenges such as stability, biocompatibility, and mechanical strength. Manufacturing methods typically involve micromolding techniques, ensuring reproducibility and scalability. Moreover, HF-MAPs hold potential for interstitial fluid sampling, aiding in diagnostic applications. Future prospects include the development of wearable biosensing devices integrated with HF-MAPs, along with scale-up manufacturing of drug-loaded HF-MAPs for clinical trials. Continually addressing regulatory concerns and optimizing patient acceptability remain essential for the successful translation of HF-MAP technology into clinical practice.