Methods of fabricating microneedle arrays using sacrificial molds, and microneedle arrays fabricated thereby

Abstract

Microneedle arrays are fabricated by providing a sacrificial mold including a substrate and an array of posts, preferably solid posts, projecting therefrom. A first material is coated on the sacrificial mold including on the substrate and on the array of posts. The sacrificial mold is removed to provide an array of hollow tubes projecting from a base. The inner and outer surfaces of the array of hollow tubes are coated with a second material to create the array of microneedles projecting from the base. The sacrificial mold may be fabricated by fabricating a master mold, including an array of channels that extend into the master mold from a face thereof. A third material is molded into the channels and on the face of the master mold, to create the sacrificial mold. The sacrificial mold then is separated from the master mold. Alternatively, wire bonding may be used to wire bond an array of wires to a substrate to create the sacrificial mold. The first material preferably is coated on the sacrificial mold by plating. Prior to plating, a plating base preferably is formed on the sacrificial mold including on the substrate and on the array of posts. The inner and outer surfaces of the array of hollow tubes preferably are coated with the second material by overplating the second material on the inner and outer surfaces of the array of hollow tubes.