A filter and a method of forming a suture structure. The filter includes layered structure(s) interior to the filter. Each layered structure includes a carbon structure comprising carbon and a coating on a surface of the carbon structure. Each layered structure may further include a heparin layer that includes heparin and is on the coating. The coating of the filter includes cellulose, PMMA, PEMA, or PHEMA. The carbon structure may include an activated charcoal layer or carbon nanotube(s). The layered structure is configured to remove a contaminant flowing through the filter. The method of forming the suture structure includes forming a film on a suture that has been previously formed on a mammal. The film includes both a coating on the suture and a heparin layer that includes heparin and is on the coating. The coating of the suture structure includes cellulose, PMMA, PEMA, or PHEMA.
