Fabrication of Dissolvable Microneedles by utilizing 3D-printed PMMA Microstamp for Transdermal Drug Delivery

抄録

For the last two decades, microneedles (typically 100~1000μm in length) have been investigated extensively as a novel technique of transdermal drug delivery for advantages such as minimally invasive, increased safety and commercially feasible. Dissolvable microneedles are more focused because the drug is encapsulated into the water-solvable carbohydrate or polymers and released into the skins after insertion, resulting in no harmful residue in human body. Micro-molding method is utilized commonly but the heat treatment for solidifying cannot guarantee the pharmaceutical activity of drug. In this research, drawing lithography was utilized for fabrication, creating three-dimensional microstructures from two-dimensional materials without complex fabrication and activity of loss of biological drugs in a few minutes even at the room temperature. The solution was composed of 20% (w/w) Hyaluronic acid (HA), 0.0015% (w/w) Rhodamine B and deionized (DI) water. The red Rhodamine B was used as model drug encapsulated in microneedles. Poly(methyl methacrylate) (PMMA) disks with micro-arrays for stamping designed in different sizes and spacings were fabricated by 3D printing technology and used to adhere the solution for drawing at the room temperature. In a result, HA microneedles arrays were fabricated with the height of 300〜500 μm and tip diameter within 50μm by using different sizes of PMMA stamp.