This proposal describes a strategy to design, prepare, and characterize surfaces with covalently attached heparin to create thrombo-resistant surfaces. Heparin is among the most frequently anti-thrombotic drugs prescribed in hospitals, but long time administration results in side effects. In the proposed research, heparin will be tethered using surface grafted PEOs. PEO chains will be components of the tri-block copolymer PEO-PPO-PEO that will be covalently attached onto the solid surfaces at the position of the PPO segment. Low molecular weight heparin (LMWH) as opposed to unfractionated free heparin will be used. Biomaterials that are currently used as implants have surfaces that are not effectively thrombo-resistant, and heparin-coated biomaterials do not behave differently than unheparinized implants in vivo. The investigators hypothesize that the reason for this result is the inadequate control of surface attached heparin (spatial and structural character of heparin).
