Biocompatible materials that have the ability to release
nitric oxide (NO) in situ at the surface-blood interface when in contact with blood. The materials which may be polymers (e.g.,
polyurethane, poly(
vinyl chloride),
silicone rubbers), metals, such as stainless steel, carbon, and the like are provided with biocatalysts or biomimetic catalysts on their surface that have
nitrite,
nitrate, and / or nitrosothiol-reducing capability. Illustratively, the catalysts are adsorbed or immobilized at the surface of the material. The catalysts can act on endogenous
nitrite,
nitrate, or nitrosothiols within the blood creating a local increase in the NO levels at the surface of the material. An illustrative enzymatic biocatalyst is mammalian
xanthine oxidase. In another illustrative embodiment, a biomimetic catalyst is a
copper (Cu(II)-ligand complex, e.g. dibenzo[e,k]-2,3,8,9-tetraphenyl-1,4,7,10-tetraaza-cyclododeca-1,3,7,9-tetraene. In some cases, lipophilic salts of
nitrite /
nitrate (e.g., tridodecylmethylammonium nitrite (TDMA+NO2− / NO3−)) or certain salts of nitrosothiols can be doped within a
polymer material, or an underlying polymeric film, to create a reservoir of nitrite or nitrosothiol that continuously leaks into the immobilized catalytic layer. Adequate levels of endogenous reducing equivalents are present within blood to provide catalytically-generated surface levels of NO that are above the threshold reportedly required to prevent
platelet adhesion or activation.