Systems and methods are provided for fabricating microneedle arrays that includes electrospun fibers preferentially disposed within the microneedles of the array. Providing the electrospun fibers preferentially in the microneedles allows for more of a drug or other substance present in the fibers to be deposited into tissue or to provide other benefits. A mold for forming the microneedle arrays includes an insulating surface layer. The insulating surface layer affects the electric field during electrospinning such that electrospun fibers are deposited preferentially within the microneedle cavities of the mold relative to the surface of the mold. A bulk material can then be applied to the mold to form the bulk of the microneedles with electrospun fibers embedded within and a backing layer to which the microneedles are attached.