Small‐Caliber Vascular Prosthesis Prototype Based on Controlled Release of Heparin from Mesochannels and Its Enhanced Biocompatibility

Abstract A novel small‐caliber vascular prosthesis prototype is proposed on the basis of a new heparin release system, that is, the controlled delivery of heparin from mesochannels. Fabrication of mesochannels on artificial biomaterials is successfully achieved through epitaxial growth of mesoporous silica nanoparticles on expanded polytetrafluoroethylene grafts, and thus heparin can be immobilized through a space limitation effect, thereby avoiding the loss of bioactivity and enabling long‐lasting release. The adsorption and release of heparin are controlled by adjusting the adsorbate–adsorbent interaction through tailoring the mesostructure. Owing to the continuous and sustained release of heparin, the performances of artificial vessels are greatly improved, thus paving a new way to prepare functional blood‐contacting biomaterials with high biocompatibility.