Relationships between antithrombogenicity and surface free energy of regenerated silk fibroin films

Silk fibroin (SF) was dissolved in calcium chloride/ethanol/water mixture (1/2/8 in mole ratio) at 70°C for 4 h. The dissolved silk fibroin was regenerated by casting the dialyzed solution into the films. The films were treated with 50% aqueous solution of methanol for different times, and their antithrombogenicity was evaluated byin vitro andin vivo tests.In vivo blood tests were made by a method of peripheral vein indwelling suture. It was found that the silk fibroin had a good anti-thrombogenicity and an absorbability even though the polymer showed foreign body reaction. Finally, the blood compatibilty of silk fibroin films which were subjected to structural change by the methanol treatment, was examined in connection with their interfacial surface energy, and a correlation between these properties was found to be present.