Body absorbable Multilayer Micro-needle Systems for Controlled Drug Delivery

Conventional hypodermic injections are widely used for drug administration due to their high therapeutic efficacy. However, they are associated with several drawbacks, including pain, needle phobia, needle-stick injuries, improper disposal, and the need for trained healthcare personnel. Microneedle-based drug delivery systems have emerged as a promising alternative, enabling painless and minimally invasive administration of therapeutic agents while improving patient compliance.
In this study, biodegradable and bioabsorbable multilayer microneedle patches were developed for controlled and sustained drug delivery. Microneedle molds were fabricated using high-resolution digital light processing (DLP) 3D printing technology. Biodegradable polymers, including alginate, gelatin, hyaluronic acid, polyvinyl alcohol (PVA), and polyvinylpyrrolidone (PVP), were employed to obtain microneedles with tunable mechanical strength and degradation behavior. The rheological properties of polymer solutions and blends were evaluated to optimize the fabrication process.
Two model drugs, 5-fluorouracil (5-FU) and lysozyme, were selected to represent chemical and biological therapeutics, respectively. Drug-loaded microparticles were produced using a microfluidic platform, enabling precise control of particle size distribution and efficient encapsulation.
The fabricated microneedles were characterized in terms of morphology, swelling behavior, degradation rate, drug release kinetics, and compression strength. Results demonstrated that polymer composition and layer configuration significantly influenced the physical, mechanical, and release properties of the microneedles. The proposed biodegradable multilayer microneedle platform offers a promising strategy for safe, patient-friendly, and efficient transdermal delivery of drugs and vaccines.