Optimal design and fabrication of a microneedle arrays patch

This research produced a microneedle array patch consisting of a biodegradable polymer. Due to guidelines for the material's failure and the mechanical properties of various skin layers, this research investigates four types of microneedles of three sizes to determine the optimal microneedle. Through numerical simulation, the insertion force and variations in the stress distribution induced by insertion of a polylactic acid (PLA) microneedle array into the skin were tabulated by software (ANSYS/LS-DYNA) in a finite element manner. A microneedle array master was manufactured through the process of a micro-electro-mechanical system (MEMS). The mold of the microneedle array employed polydimethylsiloxane (PDMS). The patch of microneedle arrays composed of PLA was manufactured using micro-hot-embossing. The optimal process parameters for fabricating microneedle arrays through micro-hot-embossing were identified by the Taguchi method. This study compared the original design sizes of microneedle arrays and those of PLA microneedle arrays by examining transfer from the PDMS mold. Through a skin puncture experiment, it was determined that the transepidermal water loss increased after the PLA microneedle array had penetrated the skin, which indicated that the PLA microneedle array decreased moisture protection by skin.