Fabrication and testing of porous Ti microneedles for drug delivery

Porous metal microneedles were fabricated by an incorporated process of cutting and wet etching. Each microneedle is comprised of many connecting microholes that can deliver drugs into organisms conveniently and efficiently. The microneedle height is larger than 400 μm, the pitch distance is about 800 μm and the microholes in each microneedle are about 20 μm in diameter. In force testing, the microneedles could resist large shear forces and pierce into skins easily; in the in vivo experiment, the insulin was efficiently injected into rats by a patch of the microneedles. The testing and the experiment demonstrated that the microneedles could deliver drugs into organisms to treat diseases without fracture.