Fabrication of hyaluronic acid hollow microneedle array

A hollow microneedles array using biodegradable hyaluronic acid as the material for the microneedle array was fabricated. We proposed a method in which gelatinous hyaluronic acid was affixed to a core and then released after drying. A polylactic acid which has high tensile strength and high affinity for hyaluronic acid was used as the core material. Using this method, we succeeded at fabricating a highly safe hollow microneedle array. An opening was formed in the needle tip by coating the tip of the core with a hydrophobic UV curable resin. The diameter of the needle tip could be reduced by using a conical core, and the needle tip was sharpened by cutting it with a femtosecond laser. The mechanical strength of hyaluronic acid hollow microneedle was evaluated using the surface of artificial skin.