Targeted delivery to the skin and the eye using microneedles

BIOT 283

Mark R. Prausnitz, prausnitz@gatech.edu, School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive, Georgia Institute of Technology, Atlanta, GA 30332-0100
Effective therapy often requires drug delivery targeted to specific tissues. Here, we designed, fabricated and studied microneedles to target delivery to the skin and the eye. Arrays of solid microneedles were coated with influenza vaccine and administered to the skin of mice. While antibody levels after a single immunization were the same after microneedle delivery to the skin compared to conventional intramuscular injeciton, memory responses generated after challenge to a lethal dose of influenza virus were significantly stronger after microneedle delivery targeting skin. In a separate study, hollow microneedles were inserted to the base of the sclera of human, pig and rabbit eyes in vitro. Injection of fluid containing fluorescent markers and polymeric particles was targeted to the suprachoroidal space (i.e., between sclera and choroid), and thereby circumferentially targeted the choroidoretinal surface within the eye, of interest for drug delivery to treat retinal disorders, such as macular degeneration.