An implantable medical device includes a bioactive material coated on a contact surface. The contact surface and bioactive material each has a defined surface energy density comprising a polar component and a non-polar component. The polar components of the surface energies are substantially matched and the non-polar components of the surface energies are substantially matched so as to allow optimised bonding and elution of the material when in situ within a patient. A method for manufacturing the device is also provided.
