Rapid formation of ultrahigh strength vascular graft: Prolonging clotting time micro-dimension hollow vessels with interpenetrating polymer networks

Cardiovascular disease is the biggest killer of human health, and reliable small diameter artificial blood vessels still remains a huge challenge. During the transplant process, small-diameter artificial blood vessels need to meet the mechanical properties of physiological environment. The blood flow volume at the transplant site is often too small to wash away the microthrombi on the vessel wall. Therefore, small-diameter artificial blood vessels are required to have a prominent anticoagulant effect. In order to realize these expectations for small diameter artificial blood vessels, we successfully developed a micro diameter (diameter = 1.5 mm) vessel with polyvinyl alcohol (PVA) and alginate (Alg) interpenetrating polymer networks (IPN) through coaxial printing. The artificial blood vessel not only shows extreme high strength, but also can simulate the vascular compliance of natural blood vessel to overcome the lack of compliance of polymer artificial blood vessel. Due to the hydrophilicity of the material, the absorption ratio of albumin/fibrin was increased. It reduces the effect of the material on platelet activation and improves the anticoagulation of the material. The artificial vessels show excellent anticoagulation when tested from in vitro to ex vivo. The artificial blood vessels could grow closely with surrounding tissues after implantation in subcutaneous tissue on the back of a rat. The artificial blood vessel can well adapt to the needs of the graft site, and promote development of micro diameter artificial blood vessel.