Substrates, optionally coated with an undercoating, having grafted thereto one or more non-fouling materials are described herein. The non-fouling, polymeric material can be grafted to a variety of functionalized substrate materials, particularly polymeric substrates and/or polymeric undercoatings immobilized on a substrate. The compositions described herein are highly resistant protein absorption, particularly in complex media and retain a high degree of non-fouling activity over long periods of time. The compositions described herein may also demonstrate antimicrobial and/or anti-thrombogenic activity. The non-fouling material can be grafted to a functionalized substrate, or optionally from an undercoating on the substrate, preferably without significantly affecting the mechanical and/or physical properties of the substrate material.
