An apparatus and method are provided for selectively applying an
agent-containing liquid coating to extremely tiny skin piercing
microprojections (10). The coating solution is applied to the skin
piercing microprojections (10) using a coating technique which selectively
coats only the skin piercing microprojections (10) and not the substrate
(12) from which the microprojections (10) extend, and then dried. The
coating method includes providing an agent-containing coating liquid and
conveying the liquid to a liquid holding surface having a coating transfer
region. The depth of the coating liquid at the coating transfer region is
precisely controlled. The microprojections are then immersed to a
predetermined level in the coating liquid. The liquid that coats the
microprojections (10) is then dried to form a solid agent-containing
coating on the microprojections (10).
