Patent ID: 6968234

Claim:
An implantable medical device, comprising: a medical unit for long term implantation in a subject; and a casing at least partially enclosing the medical unit, the casing comprising a base polymer selected from the group consisting of polyurethanes, polyurethane copolymers, fluoropolymers, polyolefins, epoxies and silicone rubbers, a polythylene oxide surface modifying end group covalently bonded to the base polymer, and a biologically active agent attached to the surface modifying end group selected from a group consisting of microbial peptide agents, antibiotics, detergents, non-steroidal anti-imflammatory drugs, cations, amine-containing organosilicones, diphosphonates, fatty acids, fatty acid salts, and wherein the biologically active agent is released in the presence of biological conditions indicative of infection by the polyethylene oxide surface modifying end group breaking off the base polymer due to oxidation casued by cellular inflammation attendant an attack by macrophages.