Fabrication of Patterned Composite Microneedles via Inkjet Printing for Enhanced Drug Delivery.

Microneedle (MN) technology offers a minimally invasive, patient-friendly alternative to conventional hypodermic injections for dermal drug delivery. However, traditional micro-molding techniques are limited by single-material fabrication, involving labor-intensive processes, excessive material waste, and scalability issues, restricting broader therapeutic applications. To address these challenges, an inkjet printing method is implemented to fabricate multi-material MN patches using gelatin and gelatin methacryloyl (GelMA) hydrogels. This technique enables precise control over hydrogel composition, allowing for MN patches with tailored mechanical strength, multi-drug incorporation, and functional enhancements achieved by integrating different materials. By tailoring gelation processes for each hydrogel type, MN structures can be customized to meet specific therapeutic needs, such as enhanced mechanical integrity or rapid dissolution for targeted drug release. Unlike conventional micro-molding, the method eliminates complex post-processing steps like centrifugation and vacuum treatment, reducing material waste and production time. Furthermore, the inkjet printing method facilitates multi-drug incorporation within a single MN patch, expanding its potential for targeted, multi-drug delivery applications. Drug delivery studies validated the efficacy of these multi-material MN patches, highlighting the potential of inkjet printing as a scalable, efficient, and cost-effective platform for advanced transdermal drug delivery systems.