Vaccine delivery via microneedle arrays

A microprotrusion array, comprising:

• an approximately planar base and a plurality of microprotrusions, each microprotrusion having an attachment point to the base and a distal tip to penetrate skin, said plurality of microprotrusions comprised of a first layer and a second layer, said first layer comprising at least one polymer different from a polymer in the second layer,
• the first layer comprised of (i) a biodegradable polymeric material, (ii) a component selected from a sugar, a sugar alcohol, a cyclodextrin, and a water-swellable polymer, and (iii) a vaccine against anthrax, said first layer disposed in at least the distal tip of each microprotrusion in the plurality of microprotrusions, and
• wherein the biodegradable polymeric material has a molecular weight of at least about 10,000 Daltons.