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...http://www.google.com/patents/US20020115559?utm_source=gb-gplus-sharePatent US20020115559 - Biocatalytic and biomimetic generation of nitric oxide in situ at substrate/blood interfacesAdvanced Patent SearchPublication numberUS2002011