Manufacture and property research of heparin grafted electrospinning PCU artificial vascular scaffolds

State of the Art of Small‐Diameter Vessel‐Polyurethane Substitutes

“…Hemocompatibility, which involves thrombosis in the lumen of blood vessels, is another problem PU small‐diameter vascular substitutes encountered. To date, numerous strategies, such as surface modification, polymer blending, and endothelialization by introducing specific peptides, have been proposed, and the short‐term hemocompatibility has been significantly improved . However, the formation of thrombosis in vascular substitutes after long‐term implantation remains a headache.…”

“…Thus, it becomes one of the most popular materials currently used for small‐diameter vascular prostheses (as shown in Figure 4 ). It was reported that PCU may also degrade under conditions of enzyme catalysis and in the presence of macrophages, but the degradation mechanisms are relatively complicated and diversified, which could be seen in the references and not explained here deliberately …”

A biomimetic orthogonal-bilayer tubular scaffold for the co-culture of endothelial cells and smooth muscle cells

“…3a, the characteristic absorption peaks of PCL were 1730 cm À1 (C]O stretching vibration) and 1170 cm À1 (C-O-C stretching vibration), 28 and those of heparin were approximately 3000-3700 cm À1 (amine stretching vibrations) and 1620 cm À1 (protonated amine vibration). 28,37 Clear absorption peaks were observed at 3290 cm À1 , 1730 cm À1 , 1620 cm À1 , and 1170 cm À1 in the heparinized PCL spectrum. 38 The peak intensity at approximately 3290 cm À1 was weaker than that of the heparin spectrum, indicating a decrease in the free hydroxyl groups on the carboxyl moiety of heparin and conrming that heparin was successfully graed onto the PCL surface.…”

Electrospun nanofiber scaffold for vascular tissue engineering

“…Heparins are highly sulfated glycosaminoglycans that inhibit the action of thrombin and clotting factor FXa [127]. Commonly used methods for incorporating heparin into vascular grafts are immobilization [94,[128][129][130][131], plasma treatment [130,132,133], and coaxial electrospinning [134,135]. Additionally, emulsion electrospinning has been utilized to incorporate heparin directly into the fibers of the graft.…”

“…Other gases can be used to graft functional groups onto the graft surface. Li et al [133] used NH 3 plasma treatment to graft amine groups to polycarbonate polyurethane (PCU) and subsequently graft heparin to the surface. In a comparison of the efficacy of heparin grafting techniques, Qui et al [130] used two immobilization techniques: aminolysis with a PEG amine linker and a polydopamine (PDA) coating for the absorption of heparin; and compared them to an allylamine plasma treatment on a PCU graft.…”