Modulation of transdermal drug delivery with coated microneedles

Schematic illustration of polyplex-coated MNs for cutaneous delivery of DNA vaccines. Intradermal vaccination of MN arrays loaded with DNA polyplexes on heparin and charge reversal pH-sensitive copolymers alternatively deposited MN arrays. The charge reversal characteristics of copolymers allowed the disassembly of layer-by-layer coating and release DNA vaccine into immune cells (Reproduced with permission from Ref. [5]).332